PLANULA

planula

(noun) the flat ciliated free-swimming larva of hydrozoan coelenterates

Source: WordNet® 3.1


Etymology

Noun

planula (plural planulae)

(biology) In embryonic development, a vesicle filled with fluid, formed from the morula by the divergence of its cells in such a manner as to give rise to a central space, around which the cells arrange themselves as an envelope; an embryonic form intermediate between the morula and gastrula.

(zoology) The larva of a hydrozoan, which is free-swimming and covered in cilia.

Source: Wiktionary


Plan"u*la, n.; pl. Planulæ. Etym: [L., a little plane.]

1. (Biol.)

Definition: In embryonic development, a vesicle filled with fluid, formed from the morula by the divergence of its cells in such a manner as to give rise to a central space, around which the cells arrange themselves as an envelope; an embryonic form intermediate between the morula and gastrula. Sometimes used as synonymous with gastrula.

2. (Zoöl.)

Definition: The very young, free-swimming larva of the coelenterates. It usually has a flattened oval or oblong form, and is entirely covered with cilia.

Source: Webster’s Unabridged Dictionary 1913 Edition



RESET




Word of the Day

22 June 2025

STRAP

(noun) an elongated leather strip (or a strip of similar material) for binding things together or holding something in position


coffee icon

Coffee Trivia

Some 16th-century Italian clergymen tried to ban coffee because they believed it to be “satanic.” However, Pope Clement VII loved coffee so much that he lifted the ban and had coffee baptized in 1600.

coffee icon