affluent [LME] From Latin affluere ‘flow towards’, affluent was used to describe water either flowing towards a place or flowing freely without any restriction. At the same time it could also mean ‘abundant’. The sense ‘wealthy’, is mid 17th century. Related words, all based on Latin fluere ‘to flow’ are fluent [L16th] and fluid [LME]; flume [ME] originally a stream; flux [LME] a state of flowing; effluent [LME] something that flows out; and superfluous [LME] ‘overflowing’.