mourn

verb

1. (ambitransitive)To express sadness or sorrow for; to grieve over (especially a death).

   “For two months, she mourned her father's passing.”

   “We mourn in black; why mourn we not in blood?”

   “Abraham came to mourn for Sarah, and to weep for her.”

   “Thane Krios: It seems there will be no one to mourn me when I die. You're the only friend I've made in ten years.”

2. (ambitransitive)To engage in the social customs of mourning; to commemorate a death and/or honour the deceased socially.

   “In that society, a spouse is mourned for one year, a parent for six months.”

3. (transitive)To utter in a sorrowful manner.
4. (intransitive)To wear mourning.

noun

1. (countable, literary, uncountable)Sorrow, grief.

   “Anone after ther cam balen / and whan he sawe kynge Arthur / he alyght of his hors / and cam to the kynge on foote / and salewed hym / by my hede saide Arthur ye be welcome / Sire ryght now cam rydynge this way a knyght makynge grete moorne / for what cause I can not telle”

2. (countable, uncountable)A ring fitted upon the head of a lance to prevent wounding an adversary in tilting.