megawatt-hour vs MWh

megawatt-hour and MWh both are nouns.

Word	Noun	Adjective	Verb	Adverb
megawatt-hour	Yes	No	No	No
MWh	Yes	No	No	No

As nouns, megawatt-hour and MWh are synonyms defined as:

megawatt-hour and MWh: a unit of energy equal to the work done by a power of 1000000 watts operating for one hour.

Other synonyms of megawatt-hour include megawatt hour.

megawatt-hour (noun)	MWh (noun)
a unit of energy equal to the work done by a power of 1000000 watts operating for one hour.	a unit of energy equal to the work done by a power of 1000000 watts operating for one hour.