IPA: //ˌpoʊstˈɔːrbɪtəl//
KK: /ˈpoʊstˌɔr.bɪ.təl/
Located at the back of the eye socket.
The postorbital bone is an important part of the skull in many animals.
Postorbital → It is formed from "post-" (meaning after or behind) and "orbital" (from Latin "orbita", meaning a path or track, specifically referring to the eye socket or orbit). The word "postorbital" refers to something located behind the eye socket.
Think of something that is located 'behind' ('post-') the 'eye socket' ('orbital') — that's what postorbital means.
No commonly confused words.