Ate a kezayit

Ate an amount equivalent to about half a matzah or half an egg, or at least 20-30 grams, which requires a concluding blessing (there are differing opinions regarding the exact amount). By extension: ate a very small amount (see also 'even a kezayit').

("The Rabbis taught: If one ate a kezayit of undercooked [meat] while it was still day – he is exempt; a kezayit of undercooked after nightfall – he is liable. If one ate a kezayit of roasted [meat] while it was still day – he did not disqualify himself from the group, a kezayit of roasted after nightfall – he disqualified himself from the group" – Pesachim 41b. Also: "He has no appetite for eating: he washed his hands, ate a kezayit for the sake of the Grace after Meals" – I.L. Peretz / Silent Souls, Minor.)

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