1. effective, effectual, efficacious

producing or capable of producing an intended result or having a striking effect

Example Sentences:
'an air-cooled motor was more effective than a witch's broomstick for rapid long-distance transportation'
'effective teaching methods'
'effective steps toward peace'
'made an effective entrance'
'his complaint proved to be effectual in bringing action'
'an efficacious law'

Synonyms

• effective
• efficacious

Similar Words

• hard-hitting
• trenchant
• impelling
• impressive
• telling
• rough-and-ready

Also See

• efficacious
• efficient
• potent
• stiff
• strong
• powerful
• useful
• utile

2. effectual, legal, sound

having legal efficacy or force

Example Sentences:
'a sound title to the property'

Synonyms

• legal
• sound