current, a sink, flow, forfeit
流 centers on continuous movement of something along a path: a current of water, a flow of things or ideas, and by extension the idea of something being carried away or lost, as in a forfeit.
flow (of a fluid or gas); stream; current
as one would expect; just as you'd expect (from); just like (someone)
exchange (e.g. cultural); interchange; interaction; mingling; mixing; coming together
sink (e.g. in a kitchen)
way; manner; style; fashion; mode
to drain; to pour; to run; to let flow; to flush; to shed (blood, tears); to spill
fashion; trend; vogue; craze; fad; popularity
to stream; to flow (liquid, time, etc.); to run (ink)
outflow; effluence; efflux; spillage; spill; discharge; haemorrhage; hemorrhage; bleeding (e.g. of ink into paper)
to be popular; to come into fashion
circulation (of money, goods, etc.); distribution
(the) mainstream
confluence (of rivers); flowing together; joining
first-class; first-rate; top-flight; top-ranking; leading; eminent; top
electric current
upper stream; upper course; upper reaches
physical distribution; distribution of goods; logistics
inflow; influx
diversion (e.g. of funds); appropriation; misappropriation
flow
downstream; lower reaches of a river
drifting; drift; being adrift
bloodshed
mid-stream; middle course
流 combines 氵 (water) with 㐬, which likely contributes the sound and the idea of flowing or moving. The character originally depicted water flowing, and the modern form preserves that association.
The left side is water 氵, and the right side 㐬 looks like a stream with a cap and a winding path. Picture water flowing along a winding current, carrying things away.
For リュウ, imagine a flowing river carrying a little canoe: the canoe's name is 'Ryu' (リュウ), and it rides the current smoothly.