Scrub, v. t. [imp. & p. p. Scrubbed; p. pr. & vb. n. Scrubbing.]
Etymology: [OE. scrobben, probably of Dutch or Scand. origin; cf. Dan. sckrubbe, Sw. skrubba, D. schrobben, LG. schrubben.]
To rub hard; to wash with rubbing; usually, to rub with a wet brush, or with something coarse or rough, for the purpose of cleaning or brightening; as, to scrub a floor, a doorplate.
3 other Webster entries under this spelling
Scrub, v. i.
To rub anything hard, especially with a wet brush; to scour; hence, to be diligent and penurious; as, to scrub hard for a living.
Scrub, n.
1. One who labors hard and lives meanly; a mean fellow. "A sorry scrub." Bunyan. We should go there in as proper a manner possible; nor altogether like the scrubs about us. Goldsmith.
2. Something small and mean.
3. A worn-out brush. Ainsworth.
4. A thicket or jungle, often specified by the name of the prevailing plant; as, oak scrub, palmetto scrub, etc.
5. (Stock Breeding)
One of the commen live stock of a region of no particular breed or not of pure breed, esp. when inferior in size, etc. [U.S.] Scrub bird (Zoöl.), an Australian passerine bird of the family Atrichornithidæ, as Atrichia clamosa; -- called also brush bird. -- Scrub oak (Bot.), the popular name of several dwarfish species of oak. The scrub oak of New England and the Middle States is Quercus ilicifolia, a scraggy shrub; that of the Southern States is a small tree (Q. Catesbæi); that of the Rocky Mountain region is Q. undulata, var. Gambelii. -- Scrub robin (Zoöl.), an Australian singing bird of the genus Drymodes.
Scrub, a.
Mean; dirty; contemptible; scrubby. How solitary, how scrub, does this town lokk! Walpole. No little scrub joint shall come on my board. Swift. Scrub game, a game, as of ball, by unpracticed players. -- Scrub race, a race between scrubs, or between untrained animals or contestants.
Shades of meaning
Fernald has no entry of its own for scrub; he lists it under cleanse.
He lists it without comment; the entries above explain its neighbors.