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Showing results for effective.
Definitions

effective

[ih-fek-tiv, ee-fek‐] / ɪˈfɛk tɪv, iˈfɛk‐ /
ADJECTIVE
successful, persuasive
Synonyms
STRONGEST
active adequate compelling competent direct efficient forceful impressive potent powerful practical successful useful valid
STRONG
effectual efficacious
WEAK
able big-wheel capable cogent convincing emphatic energetic forcible having lead in pencil live moving on the ball operative persuasive playing hardball powerhouse producing resultant serviceable serving sound striking telling trenchant virtuous wicked yielding
Antonyms
STRONGEST
helpless impotent inadequate incapable incompetent ineffective inefficient insufficient unable useless weak worthless
STRONG
unproductive unsuccessful
WEAK
fruitless inoperative
ADJECTIVE
in use at the time
Synonyms
STRONGEST
active direct dynamic
WEAK
actual current in effect in execution in force in operation operative real
Antonyms
STRONGEST
inactive
WEAK
fruitless impotent incapable ineffective inoperative unproductive useless weak

Usage

What are other ways to say effective? The adjective effective is applied to a person or a thing that has the power to, or which actually does, produce an effect: an effective boss, remedy, speech. Effectual is used especially of that which produces the effect desired or intended, or a decisive result: An effectual bombardment silenced the enemy. Efficacious suggests the capability of achieving a certain end: an efficacious plan, medicine. Efficient (applied also to persons) implies the skillful use of energy or industry to accomplish desired results with little waste of effort: efficient methods; an efficient manager. 

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

This raises the possibility that treatments targeting immune responses, such as immune-modulating drugs, could be effective for some patients.

From Science Daily • Apr. 25, 2026

"Where there are credible allegations of human trafficking, the UK state, even if no victims come forward, has a positive legal obligation to conduct a prompt, effective and independent investigation," she said.

From BBC • Apr. 24, 2026

Detection systems must be highly accurate, continuously updated, and paired with clear policies and swift takedown processes to be effective.

From Barron's • Apr. 24, 2026

Plenty of older lawmakers continue to capably serve; in some cases, seniority can make them more effective advocates for their constituents.

From Slate • Apr. 24, 2026

But it took thousands of years to build such huge and effective political structures.

From "Sapiens: A Brief History of Humankind" by Yuval Noah Harari

Vocabulary lists containing effective

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