Quick answer
Maxwell is a boy name meaning "Mack's stream".
Meaning and history
This name comes from the Scottish surname Maxwell meaning "Mack's stream", itself from the name Mack, a short form of the Scandinavian name Magnus, combined with Old English wille meaning "well, stream". A famous bearer of the surname was James Maxwell (1831-1879), a Scottish physicist who studied gases and electromagnetism. As a given name it has increased in popularity starting from the 1980s, likely because it is viewed as a full form of Max.
Notes and context
Usage: english