[1] : The Collaborative International Dictionary of English v.0.48

scrub \scrub\ skru^b, n.
   1. one who labors hard and lives meanly; a mean fellow. "a
      sorry scrub." --bunyan.
      1913 webster

            we should go there in as proper a manner as
            possible; nor altogether like the scrubs about us.
                                                  --goldsmith.
      1913 webster

   2. something small and mean.
      1913 webster

   3. a worn-out brush. --ainsworth.
      1913 webster

   4. a thicket or jungle, often specified by the name of the
      prevailing plant; as, oak scrub, palmetto scrub, etc.
      1913 webster

   5. stock breeding one of the common live stock of a region
      of no particular breed or not of pure breed, esp. when
      inferior in size, etc. u.s.
      1913 webster

   6. vegetation of inferior quality, though sometimes thick and
      impenetrable, growing in poor soil or in sand; also,
      brush; -- called also scrub brush. see brush, above.
      australia  south africa
      webster 1913 suppl. +pjc

   7. forestry a low, straggling tree of inferior quality.
      webster 1913 suppl.

   scrub bird zool., an australian passerine bird of the
      family atrichornithidae, 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 quercus
      catesbaei; that of the rocky mountain region is quercus
      undulata, var. gambelii.

   scrub robin zool., an australian singing bird of the
      genus drymodes.
      1913 webster
see also:
scrub brush brush scrub bird atrichornithidae atrichia clamosa brush bird 
scrub oak quercus ilicifolia quercus catesbaei quercus undulata scrub robin 
drymodes 

[2] : WordNet (r) 2.0

scrub brush
     n : a brush with short stiff bristles for heavy cleaning syn: scrubbing
         brush, scrubber
see also:
scrubbing brush scrubber 

Scrub >> S Words
Scrub, definition of term: Scrub
scrub_pag1.html

Brush >> B Words
Brush, definition of term: Brush
brush_pag1.html

Scrub Nurse >> S Words
Scrub Nurse, definition of term: Scrub Nurse
scrub+nurse_pag1.html

Brush Down >> B Words
Brush Down, definition of term: Brush Down
brush+down_pag1.html

Brush Aside >> B Words
Brush Aside, definition of term: Brush Aside
brush+aside_pag1.html

Brush Up >> B Words
Brush Up, definition of term: Brush Up
brush+up_pag1.html