यदुदिति स उद्गीथो यत्प्रतीति स प्रतिहारो यदुपेति स उपद्रवो यन्नीति तन्निधनम् ॥ २.८.२ ॥
In plain words
whatever is ud, that is the udgītha; whatever is prati, that is the pratihāra; whatever is upa, that is the upadrava; whatever is ni, that is the nidhana.