An expression of sympathy with another's grief:
— They sent their condolences.

synonym: commiseration.

Roget 894: courtesy; respect etc. 928; good manners, good behavior, good breeding; manners; politeness etc. adj.; bienseance, urbanity, comity, gentility, breeding, polish, presence; civility, civilization; amenity, suavity; good temper, good humor; amiability, easy temper, complacency, soft tongue, mansuetude; condescension etc. (humility) 879; affability, complaisance, pr_evenance, amability^†, gallantry; pink of politeness, pink of courtesy.    compliment; fair words, soft words, sweet words; honeyed phrases, ceremonial salutation, reception, presentation, introduction, accueil^†, greeting, recognition; welcome, abord^†, respects, devoir, regards, remembrances; kind regards, kind remembrances; love, best love, duty; empty encomium, flattering remark, hollow commendation; salaams.    obeisance etc. (reverence) 928; bow, courtesy, curtsy, scrape, salaam, kotow^†, kowtow, bowing and scraping; kneeling; genuflection etc. (worship) 990; obsequiousness etc. 886; capping, shaking hands, etc. v.; grip of the hand, embrace, hug, squeeze, accolade, loving cup, vin d'honneur [Fr.], pledge; love token etc. (endearment) 902; kiss, buss, salute.    mark of recognition, nod; nods and becks and wreathed smiles" [Milton]; valediction etc. 293; condolence etc. 915.    ... show more

Roget 896: congratulation, gratulation^†; felicitation; salute etc. 894; condolence etc. 915; compliments of the season.   

Roget 839: lament, lamentation; wail, complaint, plaint, murmur, mutter, grumble, groan, moan, whine, whimper, sob, sigh, suspiration, heaving, deep sigh.    cry etc. (vociferation) 411; scream, howl; outcry, wail of woe, ululation; frown, scowl.    tear; weeping etc. v.; flood of tears, fit of crying, lacrimation, lachrymation^†, melting mood, weeping and gnashing of teeth.    plaintiveness etc. adj.; languishment^†; condolence etc. 915.    mourning, weeds, willow, cypress, crape, deep mourning; sackcloth and ashes; lachrymatory^†; knell etc. 363; deep death song, dirge, coronach^†, nenia^†, requiem, elegy, epicedium^†; threne^†; monody, threnody; jeremiad, jeremiade^†; ullalulla^†.    mourner; grumbler etc. (discontent) 832; Noobe; Heraclitus.    ... show more

Roget 915: condolence; lamentation etc. 839; sympathy, consolation.   

Dutch: rouwbeklag, innige deelneming, compassie, medeleven, condoleantie, condoléance, deelneming
Polish: kondolencja