su·pe·ri·or bor·der of pet·rous part of tem·po·ral bone
[TA] the margin that separates the anterior and posterior surfaces of the petrous part of the temporal bone and the lateral part of the middle cranial fossa from the posterior cranial fossa. Synonym(s): margo superior partis petrosae ossis temporalis [TA], crest of petrous part of temporal bone, crest of petrous temporal bone