The Language of Clothing

[Janner52]

For my entire life blazer and sport jacket have been used interchangeably to refer to a "suit coat/jacket" that does not match the trousers.

Tan (khaki) pants & a dark blue jacket = slacks and and a blazer.

Matching pants & jacket = suit.

Matching pants, jacket & vest = three-piece suit.

I agree with the last two however sports jacket that originally referred to what was generally a tweed or similar looking jacket worn with plan trousers and in the day was referred to as casual wear.

A blazer was usually plain coloured, mostly navy blue, or striped and often with shiny buttons and an embroidered pocket badge.

This was the case in the UK.

[Touchstone]

I agree with the last two however sports jacket that originally referred to what was generally a tweed or similar looking jacket worn with plan trousers and in the day was referred to as casual wear.

A blazer was usually plain coloured, mostly navy blue, or striped and often with shiny buttons and an embroidered pocket badge.

This was the case in the UK.

Quite right, technically, but MacKenzie is also correct in noting that (in the US at least) the two terms are often used interchangeably.