You meet this word almost only inside one phrase: 'in straitened circumstances', meaning someone does not have enough money. What the phrase carries, beyond plain poverty, is a sense of having come DOWN — it is usually said of a family or a person who once had more and now has less: a widow left in straitened circumstances, a retired teacher living in straitened circumstances. The picture inside the word is narrowness: 'strait' means narrow, so your life has been squeezed into a tighter space, with fewer choices. It is formal and rather old-fashioned, the language of novels, obituaries and careful journalism; nobody says it to a friend. In ordinary speech you would say 'they're short of money', 'money's tight', 'they're struggling'. You will occasionally see it stretched to non-money situations — 'straitened budgets', 'a straitened public service', 'straitened times' — where it means resources have been cut back.

手頭拮据的、經濟困難的（尤其指從前寬裕、後來變差）。書面語，中文語感接近「家道中落」「境況拮据」。