blob vs stain

blob and stain both are nouns.

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

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

blob: make a spot or mark onto
stain: make dirty or spotty, as by exposure to air; also used metaphorically

Other hyponyms of blob include splotch, defile, maculate, sully, tarnish, bespeckle, speckle, bespatter, spatter.

blob (noun)	stain (noun)
an indistinct shapeless form	an act that brings discredit to the person who does it
	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

blob (verb)	stain (verb)
make a spot or mark onto	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