plum vs Victoria plum

plum and Victoria plum both are nouns.

Word	Noun	Adjective	Verb	Adverb
plum	Yes	No	No	Yes
Victoria plum	Yes	No	No	No

As nouns, Victoria plum is a hyponym of plum; that is, Victoria plum is a word with a more specific, narrower meaning than plum:

plum: any of numerous varieties of small to medium-sized round or oval fruit having a smooth skin and a single pit
Victoria plum: a large red plum served as dessert

Other hyponyms of plum include damson, damson plum, greengage, greengage plum, beach plum, sloe, cherry plum.

plum (noun)	Victoria plum (noun)
a highly desirable position or assignment	a large red plum served as dessert
any of numerous varieties of small to medium-sized round or oval fruit having a smooth skin and a single pit
any of several trees producing edible oval fruit having a smooth skin and a single hard stone

plum (adverb)	Victoria plum (adverb)
exactly
completely; used as intensifiers