placental

1 of 2

adjective

pla·​cen·​tal plə-ˈsen-tᵊl How to pronounce placental (audio)
1
: of, relating to, having, or occurring by means of a placenta
2

placental

2 of 2

noun

: a placental mammal : eutherian

Examples of placental in a Sentence

Recent Examples on the Web
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Adjective
Their system consisted of submerging pre-term lambs in artificial amniotic fluid, where a pumpless oxygenator, supplied by a sweep gas, mimicked placental perfusion. Srishti Gupta, Interesting Engineering, 28 Mar. 2026 In contrast, in a tree focused on marsupials, one or two placental mammals could be included at the bottom of the page for comparison. Kevin Omland, The Conversation, 9 Feb. 2026
Noun
The true placenta of the placentals allows for a longer developmental period within the protection of the womb, a factor considered to have contributed to the evolutionary success of the group. Encyclopedia Britannica, 2 Apr. 2026 In contrast, in a tree focused on marsupials, one or two placental mammals could be included at the bottom of the page for comparison. Kevin Omland, The Conversation, 9 Feb. 2026 See All Example Sentences for placental

Word History

First Known Use

Adjective

1785, in the meaning defined at sense 1

Noun

1839, in the meaning defined above

Time Traveler
The first known use of placental was in 1785

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Cite this Entry

“Placental.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/placental. Accessed 8 Apr. 2026.

Medical Definition

placental

1 of 2 adjective
pla·​cen·​tal -əl How to pronounce placental (audio)
1
: of, relating to, having, involving, or produced by a placenta
placental lactogen
placental defects
2
: of or relating to placental mammals

placental

2 of 2 noun
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