In Buddhism, the act of putting one's hands together in front of the face.

Gassho is a sign of respect, and is accompanied by bowing.

Jinmyo says:

This is a Japanese term, true for Japanese Buddhisms like Zen, Tendai, Shingon, and Jodo. Sanskrit would be anjali. But anjali is held at the heart, gassho a hand's width from the nose. A gassho is always followed by a bow, while anjali might not be.

Thanks, Jinmyo.