Definition of Nag

Verb: nag (nagged,nagging) nag

Bother persistently with trivial complaints
"She nags her husband all day long";
- peck, hen-peck
Worry persistently
"nagging concerns and doubts"
Remind or urge constantly
"she nagged to take a vacation"

Noun: nag nag

Someone (especially a woman) who annoys people by constantly finding fault
- scold, scolder, nagger, common scold
An old or over-worked horse
- hack, jade, plug