outburst vs effusion

outburst and effusion both are nouns.

Word	Noun	Adjective	Verb	Adverb
outburst	Yes	No	No	No
effusion	Yes	No	No	No

As nouns, outburst and effusion are synonyms defined as:

Other synonyms of outburst include blowup, ebullition, gush.

outburst (noun)	effusion (noun)
a sudden violent disturbance	flow under pressure
an unrestrained expression of emotion	an unrestrained expression of emotion
a sudden intense happening