stroma

American  

[stroh-muh] / ˈstroʊ mə /

noun

plural

stromata

1. Cell Biology. the supporting framework or matrix of a cell.

2. Anatomy. the supporting framework, usually of connective tissue, of an organ, as distinguished from the parenchyma.

3. Mycology. (in certainfungi ) a compact mass of tissue, in or on which the fructifications may be developed.

4. Botany. the matrix of a chloroplast containing various molecules and ions.

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stroma British  

/ ˈstrəʊmə, strəʊˈmætɪk /

noun

1. the gel-like matrix of chloroplasts and certain cells

2. the fibrous connective tissue forming the matrix of the mammalian ovary and testis

3. a dense mass of hyphae that is produced by certain fungi and gives rise to spore-producing bodies

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Other Word Forms

• stromal adjective
• stromatic adjective
• stromatous adjective

Etymology

Origin of stroma

First recorded in 1825–35; from Late Latin strōma “mattress,” from Greek strôma “bed-covering”; akin to Latin sternere “to spread, strew, ” strātum ( see stratum)

Example Sentences

The researchers examined 24 pancreatic cancer samples and found that the stroma, the connective tissue that supports the tumor, plays an active role in cancer progression rather than serving as a passive structure.

From Science Daily • Jan. 30, 2026

These energy- carrying molecules are made in the stroma where carbon fixation takes place.

From Textbooks • Jun. 9, 2022

The fluid enclosed by the inner membrane that surrounds the grana is called the stroma.

From Textbooks • Jun. 9, 2022

The fluid enclosed by the inner membrane and surrounding the grana is called the stroma.

From Textbooks • Sep. 6, 2018

An aborally-placed motor nerve-centre gives off branches to the stroma connecting the various plates of the theca and of its brachial, anal and columnar extensions, and thus co-ordinates the movements of the whole skeleton.

From Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 10 "Echinoderma" to "Edward" by Various