stub vs nubbin

stub and nubbin both are nouns.

Word	Noun	Adjective	Verb	Adverb
stub	Yes	No	Yes	No
nubbin	Yes	No	No	No

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

stub (noun)	nubbin (noun)
the small unused part of something (especially the end of a cigarette that is left after smoking)	a small nub (especially an undeveloped fruit or ear of corn)
a torn part of a ticket returned to the holder as a receipt
the part of a check that is retained as a record
a short piece remaining on a trunk or stem where a branch is lost
a small piece

stub (verb)	nubbin (verb)
strike (one's toe) accidentally against an object
clear of weeds by uprooting them
extinguish by crushing
pull up (weeds) by their roots