Definitions
1.nounOne who labors hard and lives meanly; a mean fellow.
2.nounOne who is incompetent or unable to complete easy tasks."What a scrub! Instead of washing the dishes she put the used food on her face!"
3.nounA thicket or jungle, often specified by the name of the prevailing plant"oak scrub"
4.noun(stock breeding) One of the common livestock of a region of no particular breed or not of pure breed, especially when inferior in size, etc. Often used to refer to male animals unsuited for breeding.
5.nounVegetation of inferior quality, though sometimes thick and impenetrable, growing in poor soil or in sand; also, brush.
6.nounOne not on the first team of players; a substitute.
7.adjectiveMean; dirty; contemptible; scrubby.