"Ang" literally means "high" or "lifting" and it was originally interchangeable with yang 仰 (Hanyu dacidian).
As a term used in traditional Chinese architecture, ang refers to an angled timber member used in corbel bracket sets (dougong) and placed perpendicular to the building plane (Guo 2002, 16; Chen 2010, 190).
There are five other terms used to refer to this same timber element: ang 㰇, feiang 飛昂 (lit. flying ang), ying'ang 英昂 (lit. heroic ang), xiejiao 斜角 (lit. oblique angle), and xia'ang 下昂 (lit. descending ang). In historical literature, feiang is used more often than other terms.
According to
Yingzao fashi (1103), there are two primary kinds of ang: xia'ang and shang'ang 上昂. When xia'ang are used in corner corbel bracket sets 轉角斗栱, they are called jiao'ang 角昂 or you'ang 由昂 (depending on their position). The Yingzao fashi also includes a special kind of ang: the cha'ang 插昂 (lit. inserted ang) (YZFS, 4.4b-4.7a).
There are also huagong 華栱 (lit. blossoming bracket-arms) whose "elbows" are carved to look like an ang on the exterior-side of the building in early extant structures, such as the Sage Mother Hall at Jinci from the Northern Song dynasty. These are called "pretend ang" (jia'ang 假昂) by architectural historians. This kind of timber member becomes standard in the Ming and Qing dynasties. The ang that are used in buildings and mentioned in architectural literature from the Qing dynasty are just this kind of element (Liang 1981, 21-22).
During the Song and Jin dynasties (10th-13th centuries) it was popular to make shuatou look like xia'ang. These are called slanted bracket arm-shaped shuatou (angxing shuatou 昂形耍頭) (Yu 2017, 110-115).
“昂”字的本意為高或抬起,與“仰”字通假(漢語大詞典)。昂又写作“枊”(ang)。最早見于南朝
《文選》。作為中國古代建築術語,“昂”為组织在斗栱中的一類垂直于屋身,用于出挑的斜向構件(國 2002, 16; 陳 2010, 190)。也稱為㰇、飛昂、英昂、斜角或下昂。但在歷史文獻中“飛昂”相對多見。《營造法式》(1103)中昂的種類包括“下昂” 與 “上昂”,用於轉角斗栱中的下昂稱為“角昂”和“由昂”。此外,较为特殊的還有“插昂”。(YZFS, 4.4b-4.7a)
在现存建筑实例中,宋以后出现向外一端做成昂嘴形状的平置华栱,被建筑史学者称为假昂。此类做法在明
清(17-20世纪)成为定制。清代建筑及建筑文献中的昂均指此类构件(梁 1981, 21-22)。宋
金时期(10-13世纪)也曾广泛流行将斗栱中的耍头作成下昂形式的做法,被建筑史学者称为昂形耍頭(喻 2017, 110-115)。