implacental

American  

[im-pluh-sen-tl] / ˌɪm pləˈsɛn tl /

Also implacentate

adjective

1. Zoology. having no placenta, as a monotreme or marsupial.

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noun

1. an implacental mammal.

implacental British  

/ ˌɪmpləˈsɛntəl /

adjective

1. another word for aplacental

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Etymology

Origin of implacental

First recorded in 1830–40; im- ² + placental ( def. )

Example Sentences

They differ from ordinary mammals in having the corpus callosum very small, in being implacental, and in having their young born while very immature.

From The Gutenberg Webster's Unabridged Dictionary Section M, N, and O by Project Gutenberg

Again, the implacental mammals, including the Ornithodelphia and the Marsupials, are admitted to be lower than the placental series.

From Contributions to the Theory of Natural Selection A Series of Essays by Wallace, Alfred Russel

Remarkable similarities between certain placental and implacental mammals, between the bird's-head processes of Polyzoa and the pedicellari� of Echinoderms, between Ichthyosauria and Cetacea, with very many other similar coincidences, have also been pointed out.

From On the Genesis of Species by Mivart, St. George

On land, all the indigenous mammals, except bats, belong to the lowest, or implacental division; and the insects are singularly different from those found elsewhere.

From Essays: Scientific, Political, & Speculative, Vol. I by Spencer, Herbert

Didelphia, dī-del′fi-a, n.pl. the marsupialia, or marsupial implacental mammals, one of the three sub-classes of Mammalia.—adjs.

From Chambers's Twentieth Century Dictionary (part 1 of 4: A-D) by Various