Another etymological adventure: I saw a reference to the fact that ajar was originally on char ‘on the turn’ (i.e., of a door, ‘slightly opened’), and I thought I’d investigate this mysterious char. The OED lists it as “chare, char,” saying the original but now obsolete sense ‘turn’ (whence either ‘occasion, time’ or ‘turning back, return’) is usually cher or char. An extension of this sense is ‘turn or stroke of work; an action, deed; a piece of work or business,’ and this develops the specialized meaning ‘an occasional turn of work, an odd job, esp. of household work; hence in pl. the household work of a domestic servant’ (1606 SHAKES. Ant. & Cl. IV. xv. 75 The Maid that Milkes, And doe’s the meanest chares; 1881 HUXLEY Sc. & Cult. ii. 34 Mere handicrafts and chares). But this, the “extant sense,” is “now usually CHORE.” Cue lightbulb over head.
What’s the etymology, you ask? Tangled:
OE. cerr, cierr, cyrr, masc. i- stem:—O.Teut. type *karri-z or *karzi-z… Often identified with OHG. chêr, MHG. kêr, Ger. kehr, MDu. kêr, Du. keer, masc.; besides which there is OHG. chêra, MHG. kêre, Ger. kehre, MDu. and MLG. kêre, LG. kêr str. fem.; but these represent OTeut. types *kairi-z-oz or kaizi-z, oz, and *kairâ or *kaizâ, the vowel of which has no connexion with that of the OE. word. No forms cognate to either are known outside Teutonic.