Rain (Noun and Verb) - Vine's Expository Dictionary of New Testament Words
Rain (Noun and Verb)[ A-1,Noun,G5205, huetos ]
from huo, to rain," is used especially, but not entirely, of "showers," and is found in Acts 14:17; Acts 28:2; Hebrews 6:7; James 5:7 (See EARLY and LATTER); James 5:18; Revelation 11:6 (See B).
[ A-2,Noun,G1028, broche ]
akin to B, below, lit., "a wetting," hence, "rain," is used in Matthew 7:25, Matthew 7:27. In the Sept., Psalms 68:9; Psalms 105:32. It is found in the papyri in connection with irrigation in Egypt (Deissmann, Light from the Ancient East).
[ B-1,Verb,G1026, brecho ]
akin to A, No. 2, signifies
(a) "to wet," Luke 7:38, Luke 7:44, RV (AV, to wash);
(b) "to send rain," Matthew 5:45; to rain, Luke 17:29 (of fire and brimstone); James 5:17, used impersonally (twice); Revelation 11:6, where huetos (A, No. 1) is used as the subject, lit., "(that) rain rain (not)."