etiolate

UK: /ˈiːtɪəʊˌleɪt/ US: (ē′tē ə lāt′)

WordReference Random House Unabridged Dictionary of American English © 2026

e•ti•o•late  (ē′tē ə lāt′), v., -lat•ed, -lat•ing. 
v.t. 

1. Botany, Plant Diseases to cause (a plant) to whiten or grow pale by excluding light:
   to etiolate celery.
2. to cause to become weakened or sickly;
   drain of color or vigor.

v.i. 

3. Botany, Plant Diseases (of plants) to whiten or grow pale through lack of light.

• French étioler to make pale, etiolate (plants), probably derivative, based on north, northern French dialect, dialectal forms, of standard French éteule, Old French estoble, estuble stubble; see -ate¹
• 1785–95

e′ti•o•la′tion, n. 

Collins Concise English Dictionary © HarperCollins Publishers::

etiolate / ˈiːtɪəʊˌleɪt/ verb

1. to whiten (a green plant) through lack of sunlight
2. to become or cause to become pale and weak, as from malnutrition

Etymology: 18th Century: from French étioler to make pale, probably from Old French estuble straw, from Latin stipula

ˌetioˈlation noun