踏ん反り返る

プログレッシブ和英中辞典(第4版)

ふんぞりかえる【踏ん反り返る】

❶〔そっくり返る〕straighten up and throw one's head back; draw oneself up

いすに踏ん反り返る
sit back (proudly [arrogantly]) in a chair

踏ん反り返って歩く
strut [swagger] (about)

❷〔威張る〕

踏ん反り返って意見を述べた
He gave his opinion arrogantly [in a lordly manner].

出典　小学館「プログレッシブ和英中辞典(第4版)」