'fast-growing' definitions:

Definition of 'fast-growing'

From: WordNet
adjective
Tending to spread quickly; "an aggressive tumor" [syn: aggressive, fast-growing(a), strong-growing]

Definition of 'fast-growing'

From: GCIDE
  • fast-growing \fast-growing\ adj. tending to spread quickly; -- used mostly of plants. [prenominal] [Narrower terms: {invasive (vs. noninvasive) ]
  • Syn: aggressive. [WordNet 1.5]