Definition of medusoid in English:
1Relating to or resembling a medusa or jellyfish.
- Free-living medusoid hydrozoans can be hard to tell from scyphozoans, but hydrozoan medusae generally have a muscular shelf, or velum, projecting inward from the margin of the bell.
- The trachyline Hydrozoans possess only the medusoid form.
- Although they share traits with the scyphozoans and hydrozoans, cubozoans also possess traits found in neither of the two other medusoid classes.
1.1Relating to or denoting the medusa phase in the life cycle of a coelenterate. Compare with polypoid (sense 1).
- A life cycle including both polypoid and medusoid phases that can be separate in space and scarcely overlapping in time characterizes many hydrozoans and most scyphozoans.
- Hydra never goes through a medusoid stage, and spends its entire life as a polyp.
- A few, such as Hydra, are solitary polyps that lack a medusoid stage.
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1A medusa or jellyfish.
- In colonial hydroids, the individual polyps, or zooids, are differentiated for different functions: gastrozooids feed, dactylozoids capture prey, and gonozooids give rise to medusoids with gametes.
- These are much more restricted in their distribution, possibly because they did not have as much time to disperse as the fronds and medusoids, but probably also because of environmental restrictions on their range.
- However, this is not statistically significant for the bilaterians and only weakly significant for medusoids.
Definition of medusoid in:
- US English dictionary