noun which may take the genitive case particle 'no'
Describes how something looks on the surface, often implying it may not be the true state. Used as a no-adjective before nouns.
見かけ上の問題は解決したが、根本的な原因は残っている。
The apparent problem was solved, but the root cause remains.
この機械は見かけ上は簡単そうだが、内部は複雑だ。
This machine looks simple on the surface, but its inside is complex.
Compound of 見かけ (appearance, from 見る 'to see' + かけ 'seeming') and 上 (じょう, 'in terms of').