The Tipiṭaka in Three Languages

Suññatavāra

Abhidhammapiṭaka · Dhammasaṅgaṇī · Vol. 34 · Section 344

[344] Which on that occasion is equanimity (upekkhā)? That which on that occasion is mental (cetasika), neither agreeable nor disagreeable; the neither-painful-nor-pleasant experience born of mind-contact (cetosamphassa); the neither-painful-nor-pleasant feeling (vedanā) born of mind-contact — this on that occasion is equanimity.

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

This passage also appears in 5 other places