Origin and Etymology of hilum
New Latin, from Latin, trifle
First Known Use: circa 1753
Medical Definition of hilum
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: asa: the indented part of a kidneyb: the depression in the medial surface of a lung that forms the opening through which the bronchus, blood vessels, and nerves passc: a shallow depression in one side of a lymph node through which blood vessels pass and efferent lymphatic vessels emerge
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