whole note vs semibreve

whole note and semibreve both are nouns.

Word	Noun	Adjective	Verb	Adverb
whole note	Yes	No	No	No
semibreve	Yes	No	No	No

As nouns, whole note and semibreve are synonyms defined as:

whole note and semibreve: a musical note having the longest time value (equal to four beats in common time)

whole note (noun)	semibreve (noun)
a musical note having the longest time value (equal to four beats in common time)	a musical note having the longest time value (equal to four beats in common time)