- dam (n.1)
- "water barrier," early 14c., probably from Old Norse dammr or Middle Dutch dam, both from Proto-Germanic *dammaz (source also of Old Frisian damm, German Damm), which is of unknown origin.
- dam (n.2)
- "animal mother," c. 1300, variant of dame (q.v.), also originally used, like that word, for "lady, mother;" but meanings diverged into separate spellings by 16c.
- dam (v.)
- late 15c., from dam (n.1). Related: Dammed; damming.
