(1) Ahankaar means ego. Or in other words self-identification. Maanas (heart), Buddhi and Ahankaar together comprise the inner instrument known as Antahkarn. It is through this one identifies oneself, such as "I am this body" or "that is my house". More strictly in Saankhya and Yog philosophy, it builds the "I". Because of this only Purush falsely identifies himself with material objects.

(2) According to Bhaagvat 3/2, Its another meaning is in the context of Creation. When there was nothing, first three Gun (attributes) - Sat, Raj, and Tam, appeared from Paramaatmaa through His Kaal (Time) power. Later they converted into Mahat Tattwa which was Gyaan itself. It got transformed and created Ahankaar in the form of Kaarya (action - Adhi Bhoot), Kaaran (cause - Adhyaatm) and Kartaa (doer - Adhi Daiv). It is the cause of five Bhoot, ten Indriyaan and one Man (mind).

This Ahankaar is of three types according to three Gun - Vaikaarik (Saatwik) Ahankaar, Tejas (Raajas) Ahankaar, and Taamas Ahankaar. Saatwik Ahankaar created Devtaa as the Lords of Indriya; Tejas Ahankaar created all Indriyaan; and Taamas Ahankaar created Shabd Tanmaatra - the cause of minute Bhoot (living beings).