means A narrow channel of water connecting two larger seas or bodies of water; also, by extension, a position of difficulty or hardship (often as 'dire straits').

from From the Old French 'estreit,' meaning narrow or tight, which descends from the Latin 'strictus' — the past participle of 'stringere,' to draw tight or bind. That same Latin root pulls taut a whole family of words: 'strict,' 'stringent,' 'constrict.' So a strait is literally a tightening of the sea, and to be 'in dire straits' is to feel life squeeze you the same way water gets squeezed between two shores. Note the spelling cousin 'straight' (meaning direct, unbending) is a separate word entirely, from Old English 'streht' — the two are often confused but only distantly, if at all, related.