Merriam-Webster's Collegiate® Dictionary, 11th Edition
TRICKLE
I. intransitive verb (trickled; trickling)
Etymology: Middle English trikelen, of imitative origin
Date: 14th century
1. to issue or fall in drops, to flow in a thin gentle stream,
2. to move or go one by one or little by little , to dissipate slowly ,
II. noun
Date: 1580
a thin, slow, or intermittent stream or movement