A mudra is a symbolic or ritual gesture in Hinduism and Buddhism

A mudrā (Sanskrit: मुिा , lit. "seal") is a symbolic or ritual gesture
in Hinduism and Buddhism. While some mudrās involve the entire
body, most are performed with the hands and fingers. Mudrā
(Sanskrit) is "spiritual gesture" and energetic "seal of authenticity"
employed in the iconography and spiritual practice of Indian religions
and Taoism. (Wikipedia)
Mudrās are arm, hand and body positions used in the traditions of
Hinduism and Buddhism. The great Buddha knew the use of mudrās
and is often depicted using these ritual gestures. Various Kung Fu
forms contain positions identical to these mudrās.
108 mudras are used in regular Tantric rituals. Mudras are also used
in Indian Classical Dance. There are over 200 mudras in
bharatanatyam and over 250 in mohiniattam.