guard cell


: one of the two crescent-shaped epidermal cells that border and open and close a plant stoma

Word History

First Known Use

1875, in the meaning defined above

Time Traveler
The first known use of guard cell was in 1875

Dictionary Entries Near guard cell

Cite this Entry

“Guard cell.” Dictionary, Merriam-Webster, Accessed 11 Dec. 2023.

Kids Definition

guard cell

: one of two crescent-shaped cells that form the margin of a stoma in the epidermis of a leaf and serve to open and close it

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