efficacious

[ef-i-key-shuh s]

adjective

capable of having the desired result or effect; effective as a means, measure, remedy, etc.: The medicine is efficacious in stopping a cough.

Nearby words

  1. effervescence,
  2. effervescent,
  3. effervescent salt,
  4. effete,
  5. effetely,
  6. efficaciously,
  7. efficacity,
  8. efficacy,
  9. efficiency,
  10. efficiency apartment

Origin of efficacious

1520–30; < Latin efficāci- (stem of efficāx) effectual. See efficient, -acious

Related forms
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for efficaciously


British Dictionary definitions for efficaciously

efficacious

adjective

capable of or successful in producing an intended result; effective as a means, remedy, etc
Derived Formsefficaciously, adverbefficaciousness, noun

Word Origin for efficacious

C16: from Latin efficāx powerful, efficient, from efficere to achieve; see effect

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

Word Origin and History for efficaciously

efficacious

adj.

"sure to have the desired effect" (often of medicines), 1520s, from Latin efficaci-, stem of efficax (see efficacy) + -ous. Related: Efficaciously; efficaciousness.

Online Etymology Dictionary, © 2010 Douglas Harper