hydra has definitions from the fields of zoology,astronomy,Greek mythology
1
[ noun ] (astronomy) a long faint constellation in the southern hemisphere near the equator stretching between Virgo and Cancer

Synonyms

Snake

Related terms

constellation

2
[ noun ] (Greek mythology) monster with nine heads; when struck off each head was replaced by two new ones

Examples

"Hydra was slain by Hercules"

3
[ noun ] trouble that cannot be overcome by a single effort because of its many aspects or its persistent and pervasive quality

Examples

"we may be facing a hydra that defies any easy solution"

Related terms

trouble

4
[ noun ] (zoology) small tubular solitary freshwater hydrozoan polyp

Related terms

hydrozoan genus_Hydra

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