Roe
Fish eggs. Generally, flying fish, smelt, and salmon roe are available in all sushi restaurants. "Roe" is a generic name. The roes are:
Ikura (ee-koo-rah) - salmon roe. (FYI, Ikura means ‘How much?’ in Japanese) The word Ikura is shared with the Russian word “Ikra” meaning salmon roe.
Kazunoko (kah-zoo-noh-koh) - herring roe, usually served marinated in sake, broth, and soy sauce, sometimes served raw, kazunoko konbu.
Tobiko (toh-bee-koh) - flying-fish roe, red and crunchy, often served as part of maki-zushi but also as nigiri-zushi commonly with quail egg yolk (uzura no tamago) on top uncooked.
Masago (mah-sah-goh) - capelin (smelt) roe, very similar to tobiko but slightly more orange in colour, not as common as tobiko in North America (though often caught here). Capelin, shishamo, is also served grilled (after being lightly salted) whole with the roe in it as an appetizer.