adequate to accomplish a purpose; producing the intended or expected result

effective teaching methods; effective steps toward peace.

actually in operation or in force; functioning

The law becomes effective at midnight.

producing a deep or vivid impression; striking

an effective photograph.

prepared and available for service, esp. military service.

a member of the armed forces fit for duty or active service.

the effective total of a military force.

noun

ineffectiveness , unproductivity , uselessness

noun

capability , clout , cogency , effect , efficacy , efficiency , force , forcefulness , performance , point , potency , power , punch , strength , success , use , validity , validness , verve , vigor , weight , effectuality , effectualness , efficaciousness , influence