Ran across an interesting word today doing some research on something posted elsewhere. The French word mégie 'tawing, leather-dressing' comes from Latin medico (-are, -avi, -atum) 'to heal, cure; besprinkle with juice; color, dye' (cf. 'treating a patient' vs 'treating leather'); mégisser 'to taw', mégisserie 'tawing, leather-dressing'. (In Meyer-Lübke's etymological dictionary of the Romance languages, mégie is glossed in German as "Alaun" (alum) or "Asche zum Weißgerben" (ashes for tawing). Gerben is 'to tan' and Gerber is 'a tanner' (gives new connotations to Gerber's Baby Food), leather-dresser; weißgerben, literally 'white-tanning', means 'to taw'.) Taw goes back through Middle English to Old English tawan, but does not seem to be connected with tawny from Anglo-Norman taune, past particple of taner 'to tan'; tan is from Middle English tannen via Old English from Latin tanno 'to tan' from tannum 'tanbark' which may be Celtic in origin.

There are also Gerber knives, and tanners surely do use knives.

So, taw and tawny aren't related. Pity, since I was hoping for a tawtology.