A swelling
'a swelling' is the definition.
(thesaurus)
This is the entire clue.
(Other definitions for bump that I've seen before include "Jostle" , "little impact" , "Thud down, into" , "Raised mark left by blow" , "Slang for kill - . . . . off" .)
'a swelling' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for boll that I've seen before include "swelling" , "Round seed capsule, as in cotton" , "Some grain" .)
'a swelling' is the definition.
(thesaurus)
This is the entire clue.
(Other definitions for boil that I've seen before include "Seethe - painful swelling" , "Bubble up - inflamed swelling" , "let off steam" , "7 in water" , "Cook, swelling" .)