One may grieve or mourn, regret, rue, or sorrow without a sound; he bemoans with suppressed and often inarticulate sounds of grief; he bewails with passionate utterance, whether of inarticulate cries or of spoken words.

J. C. Fernald, English Synonyms and Antonyms (1914)

Example sentences

mourn Don't mourn over the loss of your loved one too long.
lament One should not lament over past mistakes too long.
deplore One must deplore such bad behavior.
regret A time will come when you will regret your action.
sorrow To my sorrow, my father cannot attend the meeting.

Popularity over time

Word	1850 → 2019	Trend
grieve		rising
mourn		rising
lament		rising
deplore		falling
bewail		steady
regret		steady

Use in printed books, per decade from 1850 to 2019.

By length

3 letters: rue¹
4 letters: mean¹, pain¹, hurt¹, pine¹, keen¹, sigh¹, weep¹, moan¹, ache¹, wail¹
5 letters: upset², wound¹, bleed¹, annoy², mourn¹, gloom¹, wring¹, becry
6 letters: suffer², regret², sorrow², offend², repent², injure², lament², darken², bemoan², sadden², bewail, repine, deject²
7 letters: trouble², passion², anguish², torment², oppress², depress², deplore², afflict², agonize³, agonise, elegize, elegise, grieven, wayment
8 letters: complain², distress², desolate³, aggrieve², besorrow
9 letters: deprecate³

The small number after each word is its number of syllables (upset² = 2 syllables).