any disease of the mind; the psychological state of someone who has emotional or behavioral problems serious enough to require psychiatric intervention
something that provides an important central source for growth or development; "the taproot of his resentment"; "genius and insanity spring from the same taproot"
(botany) main root of a plant growing straight downward from the stem
a chess move constituting an inescapable and indefensible attack on the opponent's king
complete victory
place an opponent's king under an attack from which it cannot escape and thus ending the game; "Kasparov checkmated his opponent after only a few moves"