Also found in: Dictionary, Thesaurus, Financial, Acronyms, Idioms, Encyclopedia, Wikipedia.
Related to disk: disc


a circular or rounded flat plate; often spelled disc in names of anatomic structures.
articular disk a pad of fibrocartilage or dense fibrous tissue present in some synovial joints.
Bowman's disk one of the flat plates making up a striated muscle fiber.
choked disk papilledema.
ciliary disk pars plana.
embryonic disk (germ disk) (germinal disk) a flattened round bilaminar plate of cells in the blastocyst of a mammal, where the first traces of the embryo are seen; called also embryonic or germinal area.
herniated disk see herniated disk.
intervertebral disk the layer of fibrocartilage between the bodies of adjoining vertebrae; see also herniated disk.
intra-articular d's articular disk.
Merkel's d's small cup-shaped tactile receptors in the skin that are particularly sensitive to continuous pressure.
optic disk the intraocular part of the optic nerve formed by fibers converging from the retina and appearing as a pink to white disk in the retina; there are no sensory receptors in the region and hence no response to stimuli. Called also blind spot.
ruptured disk herniated disk.
slipped disk popular term for herniated disk.


(disk), [TA]
1. A round, flat plate; any approximately flat circular structure.
2. Synonym(s): lamella (2)
3. In dentistry, a circular piece of thin paper or other material, coated with an abrasive substance, used for cutting and polishing teeth and fillings.
Synonym(s): disk [TA]


(disk) a circular or rounded flat plate. Spelled also disc.
articular disk  a pad of fibrocartilage or dense fibrous tissue present in some synovial joints.
Bowman's disks  flat, disklike plates making up striated muscle fibers.
choked disk  papilledema.
ciliary disk  the thin part of the ciliary body.
contained disk  protrusion of a nucleus pulposus in which the anulus fibrosus remains intact.
cupped disk  a pathologically depressed optic disk.
extruded disk  herniation of the nucleus pulposus through the anulus fibrosus, with the nuclear material remaining attached to the intervertebral disk.
gelatin disk  a disk or lamella of gelatin variously medicated, used chiefly in eye diseases.
growth disk  epiphyseal plate.
Hensen's disk  H band.
herniated disk  herniation of intervertebral disk; see under herniation.
intervertebral disks  layers of fibrocartilage between the bodies of adjacent vertebrae.
intra-articular disks  fibrous structures within the capsules of diarthrodial joints.
noncontained disk  herniation of the nucleus pulposus with rupture of the anulus fibrosus.
optic disk  the intraocular part of the optic nerve formed by fibers converging from the retina and appearing as a pink to white disk; because there are no sensory receptors in the region, it is not sensitive to stimuli.
Enlarge picture
Discus opticus (optic disk).
Placido's disk  a disk marked with concentric circles, used in examining the cornea.
protruded disk , ruptured disk herniation of intervertebral disk; see under herniation.
sequestered disk  a free fragment of the nucleus pulposus in the spinal canal outside of the anulus fibrosus and no longer attached to the intervertebral disk.
slipped disk  popular term for herniation of an intervertebral disk; see under herniation.




1. A round, flattened structure in a plant or animal, such as an intervertebral disk.
2. Botany The central area bearing numerous disk flowers in the flower head of a composite plant such as a daisy.


Etymology: Gk, diskos, flat plate
1 a flat, circular platelike structure, such as an articular disk or an optic disc. Also spelled disc.
Usage notes: (informal)
an intervertebral disk.
3 media used to store data in a computerized format.


1. A round, flat plate; any approximately flat circular structure.
2. dentistry A circular piece of thin paper or other material, coated with an abrasive substance, used for cutting and polishing teeth and fillings.
3. microbiology A plate coated with an antibiotic to measure susceptibility and resistance.
4. The optic nerve head as viewed during ophthalmoscopy.
[L. discus; G. diskos, a quoit, disc]


(disk) [Gr. diskos, a dish, quoit]
A flat, round, platelike structure. Synonym: disc

anisotropic disk

A band.

articular disk

The biconcave oval disk of fibrous connective tissue that separates the two joint cavities of the temporomandibular joint on each side.

choked disk


dental disk

A thin circular paper (or other substance) used to abrade, cut, or polish teeth or dental appliances.

embryonic disk

An oval disk of cells in the blastocyst of a mammal from which the embryo proper develops. Its lower layer, the endoderm, forms the roof of the yolk sac. Its upper layer, the ectoderm, forms the floor of the amniotic cavity. The primitive streak develops on the upper surface of the disk. See: embryo for illus.

Engelmann disk

[Theodor W. Engelmann, Ger. physiologist, 1843–1909]
H band.

epiphyseal disk

A disk of cartilage at the junction of the diaphysis and epiphyses of growing long bones. Cartilage synthesis provides for growth in length; eventually the cartilage is replaced by bone.

germinal disk

A disk of cells on the surface of the yolk of a teloblastic egg from which the embryo develops. Synonym: proligerous disk; blastoderm

Hensen disk

See: Hensen, Christian Andreas Victor.

herniated disk

Rupture of the soft tissue that separates two vertebral bones into the spinal canal or adjacent spinal nerve roots. Herniation of intervertebral disks can cause back pain and, occasionally, loss of neurological function in the distribution of affected nerves. Synonym: herniated intervertebral disk; lumbar disk prolapse; slipped disk See: herniation of nucleus pulposus for illus

herniated intervertebral disk

herniated disk.
Enlarge picture
INTERCALATED DISK: Intercalated disk at the ends of adjacent cardiac muscle cells

intercalated disk

A modification of the cell membrane of adjacent cardiac muscle cells; it consists of extensive folds and intercellular junctions for electrical and mechanical linkage of contiguous cells.
See: illustration

intervertebral disk

The fibrocartilaginous tissue between the vertebral bodies. The outer portion is the anulus fibrosus; the inner portion is the nucleus pulposus. The disk is a shock absorber, or cushion, and permits movement.

M disk

M line.

Merkel disk

See: Merkel disk

optic disk

The area of the retina where the optic nerve enters.
Synonym: blind spot (1)

Placido disk

See: Placido disk

proligerous disk

Germinal disk.

slipped disk

Colloquial term for herniated disk.

tactile disk

Merkel disk.

Z disk

A thin, dark disk that transversely bisects the I band (isotropic band) of a striated muscle fiber. The thin filaments, made primarily of actin, are attached to the Z disk; the area between the two Z disks is a sarcomere, the unit of contraction.




that part of the receptacle surrounding the plant ovary which is fleshy and sometimes nectar-secreting.


A ringlike structure that fits between the vertebrae in the spine to protect the bones, nerves, and blood vessels. The outer layer is a tough, fibrous tissue, and the inner core is composed of more elastic tissue.


, disk (disk)
dentistry a circular piece of thin paper or other material, coated with an abrasive substance, used for cutting and polishing teeth and fillings.
[L. discus; G. diskos, a quoit, disc]


a circular or rounded flat plate. See also intervertebral disk.

articular disk
a pad of fibrocartilage or dense fibrous tissue present in some synovial joints. As specialized intra-articular structures they differ from articular plates in that they have nerve and blood supplies.
choked disk
embryonic disk
a flattish area in a cleaved ovum in which the first traces of the embryo are seen. Called also germinal disk.
disk explosion
the lesion produced by a sudden extrusion of non-degenerate nucleus pulposus from intervertebral disks into the cervical vertebral canal as a result of trauma.
germinal disk
the embryo in a hen egg.
intra-articular disk
articular disk.
olfactory disk
these develop on the ventrolateral aspects of the head early in fetal development. They deepen, are surrounded by the developing nasal processes, then break through into the oral cavity and become the nasal cavities.
slipped disk
the popular name for prolapse of the nucleus of an intervertebral disk.

Patient discussion about disk

Q. Is degenerative disc disease and arthritis the same thing? My husband was recently in a auto accident at work. They did a CT Scan of his head and neck. The doctor said that the CT Scan found that he has arthritis in his neck. After receiving the report ourselves to take to another doctor it reads: "There is minimal early degenerative disc disease with osteophyte formation predominately at C5-6. " My husband never had a problem with his neck before the accident

A. I was suffering from pain for 2 years and undergoing numerous test for causes when a trip to a neurologist for migraines gave me an answer. FINALLY! This was in July of this year so I am still learning and finding out about fibromyalgia but I do know in the last couple of years there has been a greater acceptance BUT there are still a lot of doctors not being supportive (from experience and talking with others) and the public in general can be unaccepting b/c you look healthy, seem to be healthy and they can not understand why you are in pain that "can't be explained!" I encourage suffers of fibro to find support within their peers! it really helps to talk to people that understand! That's what brought me to this site to start with and I am so glad I found it!

Q. What alternatives are there for DDD.De generative Disc Disease? I can't sit upright for long periods of time, at times the symptoms are worse and then days and weeks where I feel fine. When I lean into my right legit alleviates it a little but it is excruciating when I shift weight. I also have to sleep with a pillow between my legs and have to shift frequently.I have a lot of strength in my legs and back. But if I stuck in my stomach more and curve my like doing a crunch. the pain is fine.

A. Degenerative disc disease can often be successfully treated without surgery. One or a combination of treatments such as Physical therapy, chiropractic manipulative therapy (CMT), osteopathic manipulation, anti-inflammatory medications such as nonsteroidal anti-inflammatory drugs, chiropractic treatments, Traction (orthopedics), or spinal injections often provide adequate relief of these troubling symptoms.
The option of surgery may be recommended if the conservative treatment options do not provide relief within 2 to 3 months. If leg or back pain limits normal activity, if there is weakness or numbness in the legs, if it is difficult to walk or stand, or if medication or physical therapy are ineffective, surgery may be necessary. You should dicucss this with an orthopedic surgeon.

Q. what does c4-5 mild central disk bulging impinging upon cervical cord without spinal stenosis or distortion of the cord . mild righ neural foraminal narrowing from uncovertebral joint hypertropy mean

A. Well this basically means there is a very small narrowing of the cervical (your neck area) spinal canal (where the spinal cord is), however the narrowing does not cause any damage to the spinal cord, therefore probably does not cause any major symptoms involving the nerves. The c4-5 bulging part refers to the part in between the two cervical vertebras c4 and c5, in which the disc (a part in the spinal cord) is sliding a bit side-ways, but again, it does not seem to be causing any trouble.

More discussions about disk
References in periodicals archive ?
Connectivity variation can be managed through topologies of controllers, expanders, and disks, up to the limit of number of addresses supported by the active components.
The disk has got so much dust that it's unlike any other system that we've seen before," says Weinberger.
New programs for tape drives now come with a feature called installable file systems (IFS), which uses conventional computer commands to copy individual files from your hard disk to the tape and even to locate files already on the tape.
This option essentially gives users the choice of directing data to SATA disk, to tape, or both, when backing up.
He says that although the study by Quinn, Mayer, and their colleagues is the most complete test of the instability model so far, the researchers still haven't proven that a protoplanetary disk inevitably undergoes the type of instability required to form large planets rapidly.
As new files are written to disk and files updated with new and amended data, the new and altered clusters are recorded in the next available free space on the disk--and that often is far from the original file.
Finally, encryption requires about twice as much tape or disk capacity.
An early collision between our galaxy's flat disk and an intruder galaxy plausibly accounts for the extra stars that Gilmore and Reid first detected in the early 1980s, but the researchers lacked direct evidence for their model.
With this technology, documents can be digitized, indexed and stored on disk.
In the disk array configuration that consists of multiple hard disks for single parity capacity, when one hard disk damaged, the disk array can replace the damaged hard disk with a spare hard disk and restore the system's normal operating mode, a process known as "disk array recovery".
We've seen disk features before that could be due to planets .