cumquat vs kumquat tree

cumquat and kumquat tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
cumquat	Yes	No	No	No
kumquat tree	Yes	No	No	No

As nouns, cumquat and kumquat tree are synonyms defined as:

cumquat and kumquat tree: any of several trees or shrubs of the genus Fortunella bearing small orange-colored edible fruits with thick sweet-flavored skin and sour pulp

Other synonyms of cumquat include kumquat.

cumquat (noun)	kumquat tree (noun)
any of several trees or shrubs of the genus Fortunella bearing small orange-colored edible fruits with thick sweet-flavored skin and sour pulp	any of several trees or shrubs of the genus Fortunella bearing small orange-colored edible fruits with thick sweet-flavored skin and sour pulp