(assumed tropical:) Clouds (سَحَابٌ) pouring forth [rain] with vehemence. (S.)
2.
Also, and ↓بَعَاقٌ and ↓بِعَاقٌ and ↓بَاعِقٌ, (tropical:) Rain coming suddenly, or unexpectedly, with vehemence, in large drops. (K, TA.) جَمُّ البُعَاقِ, in a tradition respecting prayer for rain, means (assumed tropical:) Copious, abundant, extensive rain. (TA.)
3.
And ↓ all these four words, (assumed tropical:) A torrent vehemently driving; (K, TA;) that carries away everything. (AHn, TA.)