The word which literally means part or a limb, is often used in a technical sense. For instance, in medical sciences it stands for the body or its limb. In Jainism, it stands for a class of scriptures which are twelve in number.
In Vedic sacrifices the word aṅga indicates a subordinate rite. For instance, Paśubandha is an aṅga of Somayāga; or Prayāja is an aṅga of Darśa. These subsidiary rites may or may not produce any separate result.
More often the word is used in combination with other words getting a technical flavour. Here are some samples: pañcāṅga, the five parts of an almanac like nakṣatra or star; rājyāṅgas, the seven components of an imperial set-up like the king; senāṅgas, the four parts of an armed force like infantry; Vedāṅgas, the six subsidiary branches of knowledge which help the study of the Vedas, like Śikṣā or the science of articulation; yajñāṅgas, the vessels used in a sacrifices like sruk and sruva (spoon and ladle) and yogāṅgas, the eight steps of yoga like yama or restraint and so on.
Aṅga has often been mentioned as a country, now identified with eastern Bihar or the region around Bhagalpur in Bihar. Śiva is said to have burnt Manmatha (Cupid) to ashes here. Since Manmatha was ultimately revived, getting back his aṅgas or limbs, the place came to be known as Aṅga or Aṅgadeśa. This was once ruled by the well-known king Roma-pāda. During his regime there was once a severe famine. When the sage Ṛṣyaśṛṅga was tactfully brought into the kingdom, it rained heavily and the people were saved from starvation.
The Arthaśāstra of Kauṭilya (2.2) mentions that Aṅga is famous for well-bred elephants.
In the mythological lore, several kings by name Aṅga are mentioned: a king who had joined Duryodhana in the Kurukṣetra war; a kṣattriya hero who fought the great king Māndhātṛ; a kṣattriya king, the eldest son of Bali and Sudeṣṇā.
Karṇa, of the Mahābhārata fame, was the king of Aṅgadeśa.