grand vs big

grand is a noun but big is not a noun.

Word	Noun	Adjective	Verb	Adverb
grand	Yes	Yes	No	No
big	No	Yes	No	Yes

grand (noun)	big (noun)
a piano with the strings on a horizontal harp-shaped frame; usually supported by three legs
the cardinal number that is the product of 10 and 100

grand (adjective)	big (adjective)
used of a person's appearance or behavior; befitting an eminent person	above average in size or number or quantity or magnitude or extent
extraordinarily good or great; used especially as intensifiers	conspicuous in position or importance
the most important and magnificent in adornment	given or giving freely
of behavior that is impressive and ambitious in scale or scope	generous and understanding and tolerant
large and impressive in physical size or extent	marked by intense physical force
of high moral or intellectual value; elevated in nature or style	significant
of or befitting a lord	prodigious
ostentatiously rich and superior in quality	serious or severe
	loud and firm
	(of animals) fully developed
	in an advanced stage of pregnancy
	feeling self-importance
	exhibiting self-importance