surface form
Technical term in linguistics and natural language processing referring to the literal written or spoken form of a word or phrase, as opposed to its underlying representation.
In morphological analysis, the base form is inferred from the surface form.
深層形式 (deep form) is the abstract underlying representation, while 表層形式 is the actual realized form.
原形 (base form) is the dictionary form of a word, often derived from the surface form through analysis.
Compound of 表層 (surface layer) and 形式 (form). A calque from English 'surface form', used in linguistics.