1. A free-swimming, sexually mature form of a hydrozoan, typically resembling a jellyfish with a bell-shaped body and tentacles.
Usage: zoology; marine biology

Examples

• The hydromedusa drifted through the ocean currents, propelling itself by contracting its bell.
• Marine biologists studied the hydromedusa's feeding behavior in the laboratory.
• A hydromedusa is the mobile stage in the life cycle of many hydrozoans.
• The hydromedusa's tentacles contain specialized cells used to capture small prey.
• Unlike the sessile polyp form, the hydromedusa can move freely through the water column.