अभ्राणि सम्प्लवन्ते स हिंकारो मेघो जायते स प्रस्तावो वर्षति स उद्गीथो विद्योतते स्तनयति स प्रतिहार उद्गृह्णाति तन्निधनमेतद्वैरूपं पर्जन्ये प्रोतम् ॥ २.१५.१ ॥
In plain words
The clouds gather: that is the hiṃkāra. The rain-cloud forms: that is the prastāva. It rains: that is the udgītha. It lightens and thunders: that is the pratihāra. It ceases: that is the nidhana. This is the Vairūpa chant woven upon the rain-god.