cachet vs seal of approval

cachet and seal of approval both are nouns.

Word	Noun	Adjective	Verb	Adverb
cachet	Yes	No	No	No
seal of approval	Yes	No	No	No

As nouns, cachet and seal of approval are synonyms defined as:

cachet and seal of approval: an indication of approved or superior status

Other synonyms of cachet include seal.

cachet (noun)	seal of approval (noun)
a seal on a letter	an indication of approved or superior status
an indication of approved or superior status
a warrant formerly issued by a French king who could warrant imprisonment or death in a signed letter under his seal