difference vs difference of opinion

difference and difference of opinion both are nouns.

Word	Noun	Adjective	Verb	Adverb
difference	Yes	No	No	No
difference of opinion	Yes	No	No	No

As nouns, difference and difference of opinion are synonyms defined as:

difference and difference of opinion: a disagreement or argument about something important

Other synonyms of difference include conflict, dispute.

difference (noun)	difference of opinion (noun)
the quality of being unlike or dissimilar	a disagreement or argument about something important
a disagreement or argument about something important
a variation that deviates from the standard or norm
the number that remains after subtraction; the number that when added to the subtrahend gives the minuend
a significant change