A sorrowful cry; a lament.
Specifically, mourning.
The act of lamenting.
A group of swans.
lamentatio, (part of) a liturgical Bible text (from the book of Job) and its musical settings, usually in the plural; hence, any dirge
Emotional pain on account of something done or experienced in the past, with a wish that it had been different; a looking back with dissatisfaction or with longing.
The amount of avoidable loss that results from choosing the wrong action.
To feel sorry about (a thing that has or has not happened), afterthink: to wish that a thing had not happened, that something else had happened instead.
To feel sorry about (any thing).