Used to express that a situation is beyond one's control and must be accepted. Similar to やむを得ない, but more concise and often used in resignation.
See also: やむを得ない
It can't be helped that the game is canceled due to rain.
In this situation, we judged that some sacrifices were unavoidable.
Kanji form using 止む; rarely used in modern writing.
Kanji form using 已む; rarely used in modern writing.
Derived from the verb 止む (やむ, 'to stop') in its negative continuative form 止まず (やまず), combined with 無し (なし, 'not exist'). The phrase literally means 'there is no stopping', hence 'unavoidable'.