noun
plural -eries
[noncount] :extreme suffering or unhappiness
[count] :something that causes extreme suffering or unhappiness - usually plural
[singular] :a very unhappy or painful time or experience
When an injured or sick animal is put out of its misery, it is killed so that it no longer has to suffer. This phrase is sometimes used to refer to people as well.
[singular] Brit informal :an unhappy person who complains often or constantly :misery guts