microsphere

American  

[mahy-kroh-sfeer] / ˈmaɪ kroʊˌsfɪər /

noun

1. a tiny sphere or bead, often hollow or filled with some other substance: used for a variety of purposes, such as in building materials, cosmetics, and scientific research.

2. Medicine/Medical.

   1. a tiny hollow sphere injected into a blood vessel in order to block the flow of blood to a tumor and, in some cases, deliver chemicals or radiation to kill the tumor’s cells.

   2. a tiny hollow sphere that can be injected into the bloodstream or, sometimes, implanted into a tissue of the body: used therapeutically to deliver medicine or nutrients, or diagnostically to study the flow of blood to a certain area.

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Etymology

Origin of microsphere

First recorded in 1890–95; micro- ( def. ) + sphere ( def. )

Example Sentences

Keratin microsphere gel, consisting of keratin-based microspheres that swell in water to form a gel, has shown efficacy in promoting hair follicle growth in murine models.

From Science Daily • Feb. 29, 2024

When water-based keratin microsphere gel was applied to the shaved backs of mice, hair regrowth commenced on the second day post-application, with the rate of growth subsequently accelerating.

From Science Daily • Feb. 29, 2024

These findings represent the first evidence of the hair growth-promoting properties of keratin microsphere gel.

From Science Daily • Feb. 29, 2024

The chambers are called microsphere and megalosphere, the forms in which they occur microsphaeric and megalosphaeric forms, respectively.

From Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 6 "Foraminifera" to "Fox, Edward" by Various