Natyashastra
स्थापितोऽर्थो भवेद्यत्र समासेनार्थासूचकः । धात्वर्थवचनेनेह निरुक्तं तत्प्रचक्षते ॥ १३॥
Where the meaning is established, signifying the sense through a compound, and explained here by the root-meaning and expression, it is called a definition.
english translation
sthApito'rtho bhavedyatra samAsenArthAsUcakaH । dhAtvarthavacaneneha niruktaM tatpracakSate ॥ 13॥
hk transliteration by Sanscript