substring; partial string
Computing term for a contiguous sequence of characters within a larger string.
This function searches for the specified substring.
文字列から部分文字列を切り出す。
Extract a substring from a string.
文字列 means 'character string' in general, while 部分文字列 specifically refers to a substring or a part of a string.
Compound of 部分 (ぶぶん, 'part') and 文字列 (もじれつ, 'character string'). A straightforward technical term.