efficacious vs effectual

efficacious and effectual both are adjectives.

Word	Noun	Adjective	Verb	Adverb
efficacious	No	Yes	No	No
effectual	No	Yes	No	No

As adjectives, efficacious and effectual are synonyms defined as:

efficacious and effectual: producing or capable of producing an intended result or having a striking effect

Other synonyms of efficacious include effective.

efficacious (adjective)	effectual (adjective)
marked by qualities giving the power to produce an intended effect	producing or capable of producing an intended result or having a striking effect
producing or capable of producing an intended result or having a striking effect	having legal efficacy or force