mongrel (n.) Look up mongrel at Dictionary.com
late 15c., "mixed-breed dog," from obsolete mong "mixture," from Old English gemong "mingling" (base of among), from Proto-Germanic *mangjan "to knead together" (source of mingle), from a nasalized form of PIE root *mag- "to knead, fashion, fit." With pejorative suffix -rel. Meaning "person not of pure race" is from 1540s. As an adjective from 1570s.