tympanosquamous fissure
tym·pa·no·squa·mous fis·sure
[TA]the fissure that separates the tympanic part of the temporal bone from the squamous part; it is continuous medially with the petrotympanic fissure and the petrosquamous fissure.
Synonym(s): fissura tympanosquamosa [TA], squamotympanic fissure