as modifier Denoting a standard series of screw threads in imperial sizes.
- ‘They were also less prone to misalignment or cross threading than either the traditional design or even the Whitworth thread.’
- ‘I have an old machine which has Whitworth screws on so to find out which they were I got a Whitworth thread gauge from my local D.I.Y. shop.’
Late 19th century: from the name of Sir Joseph Whitworth (1803–87), English engineer.
We take a look at several popular, though confusing, punctuation marks.