na-adjective, noun which may take the genitive case particle 'no'
inevitable; unavoidable; bound to happen
Describes a situation or outcome that cannot be avoided; often used in formal or written contexts. Not as common as 避けられない in everyday speech.
このままでは破綻は必至だ。
At this rate, collapse is inevitable.
改革の遅れは混乱を招くことが必至である。
It is inevitable that delays in reform will cause chaos.
noun
brinkmate; inevitable checkmate
Shogi term: a position where a checkmate sequence is unavoidable regardless of the opponent's moves. Compare with 必死 (desperate situation in shogi).
See also: 必死
この局面はすでに必至がかかっている。
This position is already in brinkmate.
From 必 (certainly) + 至 (arrive). The shogi sense is a specialized use of the same characters.