placebo effect vs effect

placebo effect and effect both are nouns.

Word	Noun	Adjective	Verb	Adverb
placebo effect	Yes	No	No	No
effect	Yes	No	Yes	No

As nouns, effect is a hypernym of placebo effect; that is, effect is a word with a broader meaning than placebo effect:

placebo effect: any effect that seems to be a consequence of administering a placebo; the change is usually beneficial and is assumed result from the person's faith in the treatment or preconceptions about what the experimental drug was supposed to do; pharmacologists were the first to talk about placebo effects but now the idea has been generalized to many situations having nothing to do with drugs
effect: a phenomenon that follows and is caused by some previous phenomenon

Other hypernyms of placebo effect include consequence, event, issue, outcome, result, upshot.

placebo effect (noun)	effect (noun)
any effect that seems to be a consequence of administering a placebo; the change is usually beneficial and is assumed result from the person's faith in the treatment or preconceptions about what the experimental drug was supposed to do; pharmacologists were the first to talk about placebo effects but now the idea has been generalized to many situations having nothing to do with drugs	an outward appearance
	(of a law) having legal validity
	an impression (especially one that is artificial or contrived)
	the central meaning or theme of a speech or literary work
	a phenomenon that follows and is caused by some previous phenomenon
	a symptom caused by an illness or a drug

placebo effect (verb)	effect (verb)
	produce
	act so as to bring into existence