- a river in S Scotland, flowing NW into the Firth of Clyde. 106 miles (170 km) long.
- Firth of, an inlet of the Atlantic, in SW Scotland. 64 miles (103 km) long.
- a male given name: a Scottish family name, after the Clyde River.
- Firth of Clyde an inlet of the Atlantic in SW Scotland. Length: 103 km (64 miles)
- a river in S Scotland, rising in South Lanarkshire and flowing northwest to the Firth of Clyde: formerly extensive shipyards. Length: 170 km (106 miles)
Word Origin and History for firth-of-clyde
masc. proper name, from the family name, from the region of the Clyde River in Scotland (see Clydesdale). Most popular in U.S. for boys c.1890-1910, falling off rapidly thereafter, hence probably its use in 1940s teenager slang for "a square, one not versed in popular music or culture."