castor
Preserved but no longer current.
A hat. Mostly used in pugilistic circles. Indeed many hangers-on of the P.R. have considered that the term arose from the custom of casting the hat into the ring, before entering oneself. CASTOR was the Latin name for the animal now known as the BEAVER; and, strange to add, BEAVER was the slang for CASTOR, or hat, many years ago, before gossamer came into fashion.
Era: ca. 1874 (Victorian)
Sources & notes
Historical definition reproduced from Hotten’s The Slang Dictionary (1874, public domain; Project Gutenberg #42108, retrieved 2026-07-31). Reflects the attitudes of its era.
Common questions
What does “castor” mean?
A hat. Mostly used in pugilistic circles. Indeed many hangers-on of the P.R. have considered that the term arose from the custom of casting the hat into the ring, before entering oneself. CASTOR was the Latin name for the animal now known as the BEAVER; and, strange to add, BEAVER was the slang for CASTOR, or hat, many years ago, before gossamer came into fashion.
Is “castor” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.