blue devil

noun

1

blue devils plural : low spirits : despondency, melancholy

2

a

: a common blue-rayed aster (Aster lowrieanus) of the eastern U.S.

b

: blueweed sense 1

3

a

: either of two Australian percoid fishes (Paraplesiops gigas and P. meleagris) brightly marked with light blue dots

b

: a small brilliantly marked blue fish (Pomacentrus fuscus) of the West Indies

Word History

First Known Use

1756, in the meaning defined at sense 1

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