lubrication; smoothness
Refers to the physical property of being well-lubricated or metaphorically to smooth, frictionless operation. Often used in technical contexts or to describe smooth progress.
Regular oiling is necessary for the lubrication of machinery.
The meeting proceeded smoothly.
lubricant
lubricating oil; lubricant; lube · facilitator; smooth operator; person/thing that keeps things running smoothly
lubricating jelly
Compound of 潤 (moisten, lubricate) and 滑 (smooth, slippery). The exact historical derivation is uncertain, but the combination naturally conveys the idea of smoothness through lubrication.