A valve in an internal combustion engine mounted alongside the cylinder.
- ‘Three more prototype cars were built, chassis number A3 was the third Aston Martin ever built and is the oldest in existence with a 1.5 litre 11 hp four cylinder side valve.’
- ‘Gasoline engines with overhead valves are less polluting than those with side valves.’
- ‘Twenty of these engines had side valves; the remainder were overhead valve engines.’
We take a look at several popular, though confusing, punctuation marks.