But what about words which are untranslatable not because they mean something so specific, but because they mean so many things? My favourite (if, OK, fictional) example is Flann O'Brien's panegyric on the meanings of the Irish verb 'cur' [to put]:
There is scarcely a single word in the Irish (barring, possibly, Sasanach) that is simple and explicit. Apart from words with endless shades of cognate meaning, there are many with so complete a spectrum of graduated ambiguity that each of them can be made to express two directly contrary meanings, as well as a plethora of intermediate concepts that have no bearing on either. And all this strictly within the linguistic field. Superimpose on all that the miasma of ironic usage, poetic licence, oxymoron, plamás, Celtic evasion, Irish bullery and Paddy Whackery, and it a safe bet that you will find yourself very far from home. Here is an example copied from Dinneen and from more authentic sources known only to my little self:
Cur, g. curtha and cuirthe, m.—act of putting, sending, sowing, raining, discussing, burying, vomiting, hammering into the ground, throwing through the air, rejecting, shooting, the setting or clamp in a rick of turf, selling, addressing, the crown of cast-iron buttons which have been made bright by contact with cliff-faces, the stench of congealing badger's suet, the luminance of glue-lice, a noise made in an empty house by an unauthorised person, a heron's boil, a leprachaun's denture, a sheep-biscuit, the act of inflating hare's offal with a bicycle pump, a leak in a spirit level, the whine of a sewage farm windmill, a corncrake's clapper, the scum on the eye of a senile ram, a dustman's dumpling, a beetle's faggot, the act of loading every rift with ore, a dumb man's curse, a blasket, a 'kur', a fiddler's occupational disease, a fairy godmother's father, a hawk's vertigo, the art of predicting past events, a wooden coat, a custard-mincer, a blue-bottle's 'farm', a gravy flask, a timber-mine, a toy craw, a porridge-mill, a fair-day donnybrook with nothing barred, a stoat's stomach-pump, a broken—
But what is the use? One could go on and on without reaching anywhere in particular.(from Flann O'Brien, The Best of Myles, pp.278-279)
Myles na Gopaleen is joking (I think) but in a very nice 2012 article called "Honor Thine Author" (paywalled) the translator Fiona Elliot puts in a plea to her authors not to use the German word aufheben because
What English verb could match “aufheben,” meaning to pick something up from the floor, to save something up for later, to close a meeting, to terminate a siege, to remove restrictions, to cancel or annul, to repeal or revoke, to compensate, neutralize, offset, or elevate? (Actually, at the latest count there are forty-seven separate translations for it online at dict.cc.).(Fiona Elliott, "Honor Thine Author". Art in Translation 4:1 (2012), pp.89-98)
Happy St. Jerome's Day!