Kavyalankarasarasamgraha 7.56

7.56

iṣṭasya prākaraṇikatayā pratipādayitumabhimatasyārthasya yatra vispaṣṭatayā pratibimbaṃ sadṛśa vastu nidarśyate tatra kāvyadṛṣṭānto nāmālaṅkāraḥ /

Where a reflection, i.e., a similar entity, of an intended matter—one intended to be expressed as the subject at hand—is exhibited with clarity, there is the ornament named poetic exemplar.