ethanoyl group vs acyl group

ethanoyl group and acyl group both are nouns.

Word	Noun	Adjective	Verb	Adverb
ethanoyl group	Yes	No	No	No
acyl group	Yes	No	No	No

As nouns, acyl group is a hypernym of ethanoyl group; that is, acyl group is a word with a broader meaning than ethanoyl group:

ethanoyl group: the organic group of acetic acid (CH3CO-)
acyl group: any group or radical of the form RCO- where R is an organic group

Other hypernyms of ethanoyl group include acyl.

ethanoyl group (noun)	acyl group (noun)
the organic group of acetic acid (CH3CO-)	any group or radical of the form RCO- where R is an organic group