◎ 堂奥 táng’ào

(1) [the innermost recess of a hall]∶厅堂和内室

(2) [the interior of a country]∶腹地

(3) [profundity of thought or knowledge]∶堂的深处,喻含义深奥的意境或事理

无能老蝙蝠,乘夜出堂奥。——张来《夏日杂感》