1 of 2

adjective (1)

variants or allantoidian
: of, relating to, or derived from the allantois


2 of 2

adjective (2)

: of or relating to the Allantoidea

Word History


Adjective (1)

New Latin allantoid-, allantois + English -ean, -ian

Adjective (2)

New Latin Allantoidea + English -an

First Known Use

Adjective (1)

1855, in the meaning defined above

Adjective (2)

1878, in the meaning defined above

Time Traveler
The first known use of allantoidean was in 1855

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Dictionary Entries Near allantoidean

Cite this Entry

“Allantoidean.” Dictionary, Merriam-Webster, Accessed 6 Dec. 2023.

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