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ax·il·lar·y fos·sa

depression between the anterior and posterior axillary folds forming the floor of the axilla; after puberty, this is a site of hair growth and an abundance of sweat glands.
Synonym(s): fossa axillaris [TA], armpit


The hollow under the upper part of the arm at the shoulder.


See axilla.


The depressed hollow region located under the shoulder joint, medial to the upper arm.
Content  Axillary vessels, including the axillary artery (the extension of the subclavian artery, which becomes the brachial artery) and the axillary vein (which arises from the brachial veins and basilica vein and becomes the subclavian vein); axillary nerves; brachial plexus; lymph nodes; fat; loose connective tissue.
Muscles, anterior to posterior Pectoralis major, deltoid, biceps brachii, coracobrachialis, teres major and latissimus dorsi, and long head of triceps.
Medical significance Site of lymphatic drainage from the arm (e.g., for melanomas) and breast (e.g., for breast cancer).
Sports injuries Axillary (nerve) damage is uncommon, but well-described in contacts sports (e.g., from collisions in ice hockey or tackling in American football).

Patient discussion about armpit

Q. A lump in my armpit Hi, Last week after the shower I found a small painful lump in my right groin. I went to see a doctor and he prescribed me some antibiotics. I’ve been taking it for 5 days and the lump is still there. I’m 31, usually healthy and work-out in the gym regularly, don’t smoke or use drugs and don’t take any medications. Is that dangerous? Should I go and see another doctor?

A. What you describe sounds like enlarged lymph node. The first diagnosis that’s suspected in such case is an infection that makes it painful. The antibiotics you take need several more days to act, so currently it doesn’t sound suspicious. If the lump persist, it’d be wise to consult you doctor

Q. I located a lump on the surface of my right underarm. I think I am showing some signs of breast cancer. I am 27 years old working lady. I think I am showing some signs of breast cancer. I located a lump on the surface of my right underarm. This lump is of a cherry size and does not pain at all. But I do have pain in my breast. I had my mammogram done which showed no lump and my doctor says that there is nothing to worry and she has given me some medicines. I want to know that if everything is normal then how come these lumps came.

A. there are ways to diagnose if lumps are breast cancer or not. a lump under the forearm can be a sign of an advanced stage of cancer, but it can also mean some kind of viral infection that caused a lymph node to swell up. so if a doctor told you it's fine- he probably checked it out, and it's fine. if you still anxious - go get a second opinion.

More discussions about armpit
References in periodicals archive ?
With the disconcerting fascination of teenagers and young women with something as normal as the armpit, we hope this worrying cosmetic trend ends in 2017.
Art student Hayley Dawson stopped shaving her armpits last year and rarely shaves her legs either.
Our armpits are our focus of attention, but they contribute less than one percent of the total sweat.
In contrast, Officer Kristina Ripatti, a 10-year veteran of the force, was paralyzed in June after a slug punctured the skin below her armpit and lodged in her spine.
The hairs are growing quite nicely and I am now in a position to have my armpits styled and waxed, my sideburns permed.
Armpit is doing OK until X-Ray, a former Green Lake camper, comes around with a moneymaking scheme.
He is basically in a ball under his opponent with his left elbow at the top man's armpit and his left foot at the top man's right thigh (photo 9).
In the mid '90s, Polaroid self-portraits featuring abstracted images of the artist's face gave way to sprawling collages pieced together from repeated photographs of a single body part--an ear, armpit, forearm, and so forth.
In the same way, examine the area between the breast and armpit, and then the armpit itself.
SweatZap[TM]" is a revolutionary breakthrough in the treatment of excessive armpit sweating (axillary hyperhidrosis) which may cause "serious emotional and social problems," says Dr.
I thought everything was fine, but then seven years later I noticed a lump in my armpit.