プログレッシブ和英中辞典(第4版)の解説
たてまえ【建て前】
&fRoman1;〔棟上げ〕the completion [erection] of a framework；〔儀式〕a roof-raising ceremony
来週は建て前だ
We will have the roof-raising ceremony next week.
&fRoman2;〔表向きの方針，主義〕
建て前と本音はしばしば一致しない
Principle and practice often differ.
親睦は建て前で本当は自分が飲みに行きたいのだろう
He says it is to promote friendship, but actually he just wants an excuse to go out drinking.