Other forms: pinstripes
A pinstripe is a very fine parallel line woven into cloth. A pinstripe suit, chalk stripe or pinstripe, fine pinstripes.
It is finer than a chalk stripe, which is the wider and softer-edged kind. The pinstripe suit is the uniform of banking and of the City in every cartoon, which is why wearing one signals something whether or not it was meant to.
1nounpinstripeVery fine parallel lines woven into cloth.
“He wore a dark blue suit with a thin white pinstripe.”
pinstripe is a pattern.
Pin plus stripe, from the tailoring trade of the nineteenth century.
From pin + stripe.
Etymology from Wiktionary, CC BY-SA
Practised in Colours & Patterns