Well....I don't know how helpful this'll be, but from my copy of Origins: A Short Etymological Dictionary of Modern English, by Eric Partridge

sphinx, whence, anl, the adjj sphingal and sphingine.
1. Orig. the Sphinx of Thebes, an oracular divinity, hence any such divinity, esp if a poser of difficult riddles, hence any enigmatic person--cf the Sphinx of Giza, near Cairo, a Gr naming of an Eg image--sphinx has come into both F and E -- through L-- from Gr (Greek characters I don't know how to reproduce), gen (more Greek characters), Sphingos: from sphingein, to bind tightly, to squeeze or throttle perh cf--without n--ON spikr, a nail, and Let spaiglis, spaigle, a forked stick for catching crayfish, and --without p(h)--MIr sen (? for *spig-no-), a net: IE r, *spheig-,, var sphig- to bind. (Hofmann.)
2. Gr sphingein has another derivative: sphinkter (Greek characters), whence LL sphincter, E sphincter, the sphincter-muscle, which is contractile.

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It is hard to convey five-dimensional ideas in a language evolved to scream defiance at the monkeys in the next tree. -- The Science of Discworld III: Darwin's Watch, by Terry Pratchett, Ian Stewart & Jack Cohen