stain vs mud stain

stain and mud stain both are nouns.

Word	Noun	Adjective	Verb	Adverb
stain	Yes	No	Yes	No
mud stain	Yes	No	No	No

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

Other hyponyms of stain include scorch, bloodstain, iron mold, iron mould, oil stain, tarnish.

stain (noun)	mud stain (noun)
an act that brings discredit to the person who does it	a stain produced by mud
a soiled or discolored appearance
a symbol of disgrace or infamy
anything regarded as making something unclean
(microscopy) a dye or other coloring material that is used in microscopy to make structures visible

stain (verb)	mud stain (verb)
produce or leave stains
color with a liquid dye or tint
color for microscopic study
make dirty or spotty, as by exposure to air; also used metaphorically