köken: Inherited from Middle French doigt, doit, from Old French doit, doi, from Latin digitus, ultimately from Proto-Indo-European *deyǵ- (“to show, point out, pronounce solemnly”). The -g- was added to the spelling in Middle French after the Latin form and in order to distinguish from the verb form doit.
aile: à deux doigts, au doigt et à l'œil, au doigt mouillé, comme les doigts de la main, compter sur les doigts de la main, compter sur les doigts d'une main, connaître sur le bout des doigts, croiser les doigts, doigt de pied, doigt d'honneur
to fish hook: to perform a sexual manoeuvre in which a finger or fingers are used to form an improvised hook inside an orifice, vagina, etc; to finger; to fingerbang.
köken: From ตก (dtòk, “to angle”) + เบ็ด (bèt, “fishhook”); probably calque of English fishhook.