Dictionary.com
Thesaurus.com

indeciduous

American  
[in-di-sij-oo-uhs] / ˌɪn dɪˈsɪdʒ u əs /

adjective

Botany.
  1. not deciduous, as leaves.

  2. (of trees) evergreen.


indeciduous British  
/ ˌɪndɪˈsɪdjʊəs /

adjective

  1. (of leaves) not deciduous

  2. a less common term for evergreen

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of indeciduous

First recorded in 1640–50; in- 3 + deciduous