First of all, sound the trumpets: Polyglot Vegetarian has a new post up, just the second in the last year! The post, Green Bean, starts with restaurant menus and a detailed discussion of Chinese characters and winds its way to the main theme, the etymology of haricot. I’ll quote just enough to whet your appetite and send you over there for the full meal (there are many, many links in the quoted chunk that I won’t bother trying to reproduce):
The etymology of haricot is uncertain, with contenders from three different continents.
Haricot is a pair of homonyms: haricot de mouton is a lamb stew, from a verb harigoter meaning to cut into small pieces. The Ménagier de Paris (ca. 1393) has Hericot de mouton (II, 148). François Génin derives (Récréations philologiques, I. p. 50) this haricot from Latin aliquot ‘a few’ and Littré (s.v.) quotes the Comtesse de Bassanville as proposing Arabic hali-gote (I’m not sure what this is). More sensible sources derive harigoter from Old Low Franconian *hariôn ‘to mess up’, related to the English verb harry.
The idea that haricot beans are so-called because they came to be used in haricot stew is a bit far-fetched, particularly since beans do not seem to be a common ingredient. Even more so is Alexandre Dumas (père) ‘s claim that the stew originally was meat and beans, until “l’un des deux ingrédients a été détrôné par les navets” ‘one of the ingredients was dethroned by turnips’ (Grand dictionnaire de cuisine, s.v.). More likely is that the form of the earlier stew word influenced the later bean word.
Haricot beans (there will be no more about meat) first appear in the mid-17th century. Before then, such beans were faséoles, from Latin Phaseolus (now the name of the genus), like English fasels. [...]
The detailed discussion of various possible sources is vintage Polyveg; it ends:
I don’t know the stand of more modern specialized works (and would welcome pointers). The OED still has “Origin uncertain: see Littré,” while we wait for them to make their way around to the H’s. The Oxford dictionary of English Etymology has “perh. – Aztec ayacotli.” The Petits Robert and Larousse stick with French harigoter. French Wikipedia, s.v. Haricot and Phaseolus, is somewhat uncommitted, listing some of the alternatives given above.
If anyone has pointers, now would be the time to share them.