Straight - strait
From Hull AWE
- Straight is by far the more common. If in doubt, risk this spelling. It means 'without deviation'. (Euclid, the famous Greek geometer, defines a straight line as 'the shortest possible distance between two points'.)
- Etymological note: straight comes from the Middle English streȝt or straȝt, the participial adjective of the verb strecchen, 'to stretch'. Its earliest meaning appears to have been "Extended at full length" (OED, 1917). It rapidly became " Not crooked; free from curvature, bending, or angularity" (ibid.).
- The adjective strait means 'narrow' or 'constrained'. It is archaic, and is rarely used in modern English other than in a few regular phrases, such as 'straitjacket' (a device used to hold violent people in control) and 'strait-laced', meaning 'very controlled' and 'disapproving of loose behaviour'. (Originally, this referred to corsets.) The most common use of strait in modern English is as a noun, meaning 'a narrow passage of water', as in the Straits of Dover. It is occasionally used figuratively, as in the phrase 'He was in dire straits', where it means 'He was in great difficulty'.