adjective (1)
variants: or allantoidian \ ¦alən‧¦tȯidēən , ¦aˌlan‧-​ ; ə¦lantə¦wid-​ \

Definition of allantoidean

 (Entry 1 of 2)

: of, relating to, or derived from the allantois


adjective (2)
\ " \

Definition of allantoidean (Entry 2 of 2)

: of or relating to the Allantoidea

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First Known Use of allantoidean

Adjective (1)

1855, in the meaning defined above

Adjective (2)

1878, in the meaning defined above

History and Etymology for allantoidean

Adjective (1)

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

Adjective (2)

New Latin Allantoidea + English -an

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Time Traveler for allantoidean

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The first known use of allantoidean was in 1855

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Cite this Entry

“Allantoidean.” Dictionary, Merriam-Webster, Accessed 3 Dec. 2020.

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