Hydra vs. Obelia

Hydranoun

Any of several small freshwater polyps of the genus Hydra and related genera, having a naked cylindrical body and an oral opening surrounded by tentacles.

Hydranoun

A complex, multifarious problem or situation that cannot be solved easily and rapidly.

Hydranoun

A serpent or monster in the lake or marsh of Lerna, in the Peloponnesus, represented as having many heads, one of which, when cut off, was immediately succeeded by two others, unless the wound was cauterized. It was slain by Hercules. Hence, a terrible monster.

Hydranoun

Hence: A multifarious evil, or an evil having many sources; not to be overcome by a single effort.

Hydranoun

Any small fresh-water hydroid of the genus Hydra, usually found attached to sticks, stones, etc., by a basal sucker.

Hydranoun

A southern constellation of great length lying southerly from Cancer, Leo, and Virgo.

Hydranoun

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

Hydranoun

a long faint constellation in the southern hemisphere near the equator stretching between Virgo and Cancer

Hydranoun

trouble that cannot be overcome by a single effort because of its many aspects or its persistent and pervasive quality;

Hydranoun

small tubular solitary freshwater hydrozoan polyp

Obelianoun

(zoology) Any of various colonial marine hydroids of the genus Obelia.

Obelia

Obelia is a genus of hydrozoans, a class of mainly marine and some freshwater animal species that have both polyp and medusa stages in their life cycle. Hydrozoa belongs to the phylum Cnidaria, which are aquatic (mainly marine) organisms that are relatively simple in structure.