See pyai below.
pyai or cl. 1. Ā. ([Dhātup. xxii, 68]; [xiv, 17]) pyā́yate (pf. papye Gr.; aor. apyāyi, [ib.]; apyāsam, [AitĀr.]; Prec. pyāyiṣīmahi or pyāsiṣīmahi, [AV.]; [VS.]; [Br.]; fut. pyāsyate or pyāyiṣyate Gr.; pyātā, pyāyitā, [ib.]), to swell, be exuberant, overflow: Caus. pyāyáyati, °te, [AV.] &c.; (Pass. pyāyyáte, [Br.]) to make overflow, fill up (mostly in comp. with ā- See ā-pyai; cf. √ pi, pī).