Meaning
押し寿司 (おしずし, Oshizushi) is Oshizushi — a Japanese food (sushi and sashimi).
What is Oshizushi?
Oshizushi ("pressed sushi"), also known as hako-zushi (箱寿司, "box sushi"), is from the Kansai region, a favorite and specialty of Osaka. A block-shaped piece is formed using a wooden mold. The cook lines the bottom of the mold with the toppings, covers them with sushi rice, and then presses the lid of the mold down to create a compact, rectilinear block. The block is removed from the mold and then cut into bite-sized pieces. In oshizushi , all the ingredients are either cooked or cured. Raw fish is never used. Note that due to rendaku consonant mutation, sushi is spelled with zu instead of su whenever a prefix is attached, such as in this dish.