Ashi, You-iri (足、葉入り) refers to the presence of ""Ashi"" and ""You"" in the blade of a Japanese sword.

""Ashi"" (足) is a term used to describe a feature that appears in the blade of a Japanese sword. It refers to a pattern that extends from the edge of the blade towards the tip, appearing as if it is pointing. If the tip of the ""Ashi"" is pointing towards the tip of the blade, it is called ""Ha-ashi"". If it is pointing towards the edge of the blade, it is called ""Ji-ashi"". However, in modern times, ""Ha-ashi"" is simply referred to as ""Ashi"". It is also said that the names ""Ha-ashi"" and ""Ji-ashi"" were reversed in the past.

""You"" (葉) is a term used to describe a feature that appears in the blade of a Japanese sword. It refers to an elliptical pattern that is scattered throughout the blade. In ancient sword literature, it was also called ""pointed Ashi"", and it was named ""You"" because the scattered pattern looks like falling leaves.

In sword terminology, the overall appearance of ""Ashi"" and ""You"" in the blade pattern is expressed as ""Ashi, You-iri"". When appreciating the blade pattern, it is recommended not only to observe the temper line (Nioiguchi: the outline of the blade pattern), but also to carefully observe the ""Ashi"" and ""You"" that appear in the blade.