efficacious
adj. US //ˌɛfəˈkeɪʃəs// UK //ˌɛfɪkˈeɪʃəs// ef·fi·ca·cious
From Old French efficacieux, from Latin efficāx (“efficacious”) + -ous, from efficere (“to effect, to accomplish”); see effect.
From Old French efficacieux, from Latin efficāx (“efficacious”) + -ous, from efficere (“to effect, to accomplish”); see effect.
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