Śruti is scripture regarded as revealed, heard by ancient seers rather than composed by human authors. It comprises the Vedas, including the Upaniṣads, and is the highest authority in Hindu thought on matters beyond perception and inference. It is distinguished from smṛti, tradition that is remembered.
Śruti
“That which is heard”: the revealed scripture of Hinduism, chiefly the Vedas and Upaniṣads.
Also: Shruti, Sruti