Either of two annual herbaceous plants of the genus Sesamum (S. Indicum, and S. orientale), from the seeds of which an oil is expressed; also, the small obovate, flattish seeds of these plants, sometimes used as food. See Benne. [1913 Webster]

Open Sesame, the magical command which opened the door of the robber's den in the Arabian Nights' tale of “The Forty Thieves;” hence, a magical password. -- Sesame grass. (Bot.) Same as Gama grass.

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OXFORD DICTIONARY

sesame, n. Bot.
1 an E. Indian herbaceous plant, Sesamum indicum, with seeds used as food and yielding an edible oil.
2 its seeds.

Idiom

open sesame a means of acquiring or achieving what is normally unattainable (from the magic words used in the Arabian Nights' Entertainments).

Etymology

L sesamum f. Gk sesamon, sesame

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