Search the Dictionary

Of or pertaining to the two sides of a central area or organ, or of a central axis; as, bilateral symmetry in animals, where there is a similarity of parts on the right and left sides of the body.

State of being bilateral.

A division of Mollusca remarkable for the bilateral symmetry of the organs and the arrangement of the nerves.

One of the two halves of bilaterally symmetrical animals; one of any opposite symmetrical or homotypic parts in animals and plants.

Not symmetrical; wanting proportion; esp., not bilaterally symmetrical. Huxley.

Want of symmetry, or proportion between the parts of a thing, esp. want of bilateral symmetry.

(Zoöl.) A peculiar early larval stage of certain starfishes, having a bilateral structure, and swimming by means of bands of vibrating cilia.

An order of holothurians mostly found in the deep sea. They are remarkable for their bilateral symmetry and curious forms. [Written also Elasmopoda.]

The style of the epigram. Antithesis, i. e., bilateral stroke, is the soul of epigram in its later and technical signification. B. Cracroft.

Situated in the middle; lying in a plane dividing a bilateral animal into right and left halves; -- said of unpaired organs and parts; as, median coverts. Median line. (a) (Anat.) Any line in the mesial plane; specif., either of the lines in which the mesial plane meets the surface of the body. (b) (Geom.) The line dra…

ropodaScaphopoda, and Lamellibranchiata, or Conchifera. These animals have an unsegmented bilateral body, with most of the organs and parts paired, but not repeated longitudinally. Most of them develop a mantle, which incloses either a branchial or a pulmonary cavity. They are generally more or less covered and protect…

Symmetrical bilaterally; -- said of organisms, or parts of organisms, capable of division into two symmetrical halves only in a single plane.