spoke (wheel)
輻 centers on the spokes of a wheel, the rods that connect the hub to the rim.
輻 combines 車 (vehicle, wheel) with 畐, which likely contributes the sound フク and may relate to fullness or spreading, suggesting spokes radiating from a hub.
The left side 車 is a wheel, and the right side 畐 looks like a container with lines spreading out. Picture a wheel with spokes radiating from the center like lines from a full container.
For フク, imagine a wheel with spokes that look like the strokes of 福 (ふく, fortune) radiating outward: 福 -> フク, and the spokes bring good fortune to the wheel.
radiation
congestion; overcrowding; pile-up
port congestion
bremsstrahlung; X-rays produced when fast electrons pass through matter
solar radiation
ERP; effective radiated power
explicit congestion notification
spoke
radiant energy
radiant point
radiant heat; photothermal
radiation; radiant rays
emissive power; emissivity
congestion control (in a network)
congested state (of a network); congestion
black-body radiation