The origin of the name seems to be the Scottish river Clyde, but its meaning is far from certain.
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Perhaps not! >>>>>>>> Clyde is scots-gaelige for: Heard from afar. The river Clyde means a loud river heard from a distance. The Firth (of Clyde) means a fjord-like deep inlet (not a shallow delta) to the river near the sea. Clywwd, is also welsh-brythonic for: Loud or loudly. Clwwd is cornish pehaps for: warm. These gaeilige, welsh, and cornish words were "anglicanized" by germanic (Angle Saxon Dane) invaders into Britain.
Gaelic languages are from an Indo-European stock becoming distinct in Galatia (in modern Turkey) before; Persian adminstation, Greek trade and Roman colonialism, among other influences moved the languages and peoples ever westward into Gaul (modern France). These languages included what would later evolve into brythonic (Brittany-Gaul-France-Britain) Cornish-(Cornwall and southern Britain) Welsh (Wales) Gaelige (Eire-ireland Gaelic-Scots-Pict).
Gaulic- Gaelige- Gaelic are somewhat interchangeable terms.
Modern English is an interesting evolutionary blend of ancient (Germanic-Gaelige-French Romance) languages that is barely similar to the middle english, our language just 500-600 years ago. Modern English is a highly dialected language but most speakers can easily communicate with other speakers.
Modern French is less Gaulic (gaelic-gaeilige-brythonic) and more (due to Roman-Latin influences) Romance-Frankish-Germanic. But is still widely dialected (eg. burgundian -provencal- catalan).