plural bdelloids
: any of a class (Bdelloidea) of rotifers that reproduce by parthenogenesis and are known to only exist as females
With some 360 described species, bdelloids are the largest class of multicelled animal that reproduces asexually.Henry Fountain, New York Times, 23 May 2000

Note: Bdelloids inhabit both terrestrial and benthic environments. They include forms that swim freely using a ciliated disk and other forms that creep like a leech by alternating attaching their head and tail ends to a surface.

bdelloid adjective
This group of tiny water creatures, called bdelloid rotifers, is thriving in fresh water and soggy land worldwide despite, seemingly, no sex for at least 40 million years. Susan Milius, Science News, 28 June 2003
… corresponding gene copies in individual bdelloid clones can differ by as much as 49% … Natalia N. Pouchkina-Stantcheva et al., Science, 12 Oct. 2007

Word History


from the base of New Latin Bdelloida or Bdelloidea bdelloidea

First Known Use

1959, in the meaning defined above

Time Traveler
The first known use of bdelloid was in 1959

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Dictionary Entries Near bdelloid

Cite this Entry

“Bdelloid.” Dictionary, Merriam-Webster, Accessed 23 May. 2024.

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