[ verb dee-foh-lee-eyt; adjective dee-foh-lee-it, -eyt ]

verb (used with object),de·fo·li·at·ed, de·fo·li·at·ing.
  1. to strip (a tree, bush, etc.) of leaves.

  2. to destroy or cause widespread loss of leaves in (an area of jungle, forest, etc.), as by using chemical sprays or incendiary bombs, in order to deprive enemy troops or guerrilla forces of concealment.

verb (used without object),de·fo·li·at·ed, de·fo·li·at·ing.
  1. to lose leaves.

  1. (of a tree) having lost its leaves, especially by a natural process.

Origin of defoliate

1785–1795; <Medieval Latin dēfoliātus, past participle of dēfoliāre, equivalent to Latin dē-de- + foli(um) leaf + -ātus-ate1

Other words from defoliate

  • de·fo·li·a·tion, noun
  • de·fo·li·a·tor, noun
  • un·de·fo·li·at·ed, adjective

Words Nearby defoliate Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use defoliate in a sentence

  • When neglected for two or three years, they often defoliate large trees.

    Soil Culture | J. H. Walden

British Dictionary definitions for defoliate


  1. to deprive (a plant) of its leaves, as by the use of a herbicide, or (of a plant) to shed its leaves

  1. (of a plant) having shed its leaves

Origin of defoliate

C18: from Medieval Latin dēfoliāre, from Latin de- + folium leaf

Derived forms of defoliate

  • defoliation, noun
  • defoliator, noun

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