hilum

noun

hi·​lum ˈhī-ləm How to pronounce hilum (audio)
plural hila ˈhī-lə How to pronounce hilum (audio)
1
: a scar on a seed (such as a bean) marking the point of attachment of the ovule
2
: a notch in or opening from a bodily part suggesting the hilum of a bean

Word History

Etymology

New Latin, from Latin, trifle

First Known Use

circa 1753, in the meaning defined at sense 1

Time Traveler
The first known use of hilum was circa 1753

Rhymes for hilum

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Browse Nearby Words

Hilton Head Island
hilum
Hilversum
See all Nearby Words

Cite this Entry

“Hilum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hilum. Accessed 7 Jul. 2026.

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Kids Definition

hilum

noun
hi·​lum ˈhī-ləm How to pronounce hilum (audio)
plural hila -lə How to pronounce hilum (audio)
: a scar on a seed at the point of attachment of the ovule

Medical Definition

hilum

noun
hi·​lum ˈhī-ləm How to pronounce hilum (audio)
plural hila -lə How to pronounce hilum (audio)
1
: a scar on a seed (as a bean) marking the point of attachment of the ovule
2
: a notch in or opening from a bodily part suggesting the hilum of a bean especially when it is where the blood vessels, nerves, or ducts leave and enter: as
a
: the indented part of a kidney
b
: the depression in the medial surface of a lung that forms the opening through which the bronchus, blood vessels, and nerves pass
c
: a shallow depression in one side of a lymph node through which blood vessels pass and efferent lymphatic vessels emerge
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