noun which may take the genitive case particle 'no', adverb
Describes a situation where something is officially or formally the case, but not in reality. Often used with titles, positions, or statuses that lack real power or substance.
彼は名目上の社長に過ぎない。
He is merely the nominal president.
その会社は名目上は独立しているが、実際は大企
The company is nominally independent, but in reality it's a subsidiary of a large corporation.
名目上 means 'in name only' or 'nominally', the direct opposite of 事実上, which means 'in effect' or 'in practice'.
Compound of 名目 (name, title, nominal) + 上 (suffix meaning 'in terms of' or 'from the standpoint of').