उद्दिष्टस्य तत्त्वव्यवच्छेदको धर्मो लक्षणम् ।
uddiṣṭasya tattva-vyavacchedako dharmo lakṣaṇam |
(Vātsyāyana’s Nyāya-bhāṣya on Nyāya-sūtra: 1.1.3)
“A characteristic distinguishing of the nature of a stated object [from the nature of all other objects] is [called] a lakṣaṇa.”