Kortik

Kortik (Ко́ртик) may be
 * the Russian for naval dirk
 * a nickname for Kashtan CIWS, a weapons system of the Russian navy
 * a 1948 children's book by Anatoly Rybakov, translated into English as The Dirk
 * Kortik (1954 film), an adaptation of Rybakov's book, by Vladimir Vengerov and Michael Schweitzer
 * Kortik (1973 film), an adaptation of Rybakov's book for TV by Nikolai Kalinin