plural actinulas or actinulae
: a creeping larva of the hydroid generation of certain coelenterates (as Tubularia) that finally attaches and develops into a polyp

Word History


New Latin, from actin- + -ula

First Known Use

1864, in the meaning defined above

Time Traveler
The first known use of actinula was in 1864

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Dictionary Entries Near actinula

Cite this Entry

“Actinula.” Dictionary, Merriam-Webster, Accessed 24 Jun. 2024.

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