nigiri
nigiri-sushi

1. (n) Japanese rice balls, often garnished with sesame seeds or wrapped partly in laver (seaweed, sometimes sweetened). Nigiri-sushi (pronounced "nigiri-zushi") is the more formal name for sushi, morsels of food placed on a sushi rice (vinegar, mirin and sugar flavoured) ball.

   Rice balls are usually tubular or triangular shaped. Nigiri can be plain, but will often contain some additional material in the centre, such as shoyu flavoured bonito flakes, or umeboshi.