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n. pl. tubifex or tu·bi·fex·es
Any of various small slender reddish freshwater worms of the genus Tubifex, often used as food for tropical aquarium fish.
n, pl -fex or -fexes
(Animals) any small reddish freshwater oligochaete worm of the genus Tubifex; it characteristically lives in a tube in sand and is used as food for aquarium fish
[C19: from New Latin, from Latin tubus tube + facere to make, do]
tu•bi•fex(ˈtu bəˌfɛks, ˈtyu-)
n., pl. -fex•es, (esp. collectively) -fex.
any small bottom-dwelling annelid worm of the genus Tubifex, often used as food for aquarium fish.