yóu
oil
Phonosemantic compound. 氵 represents the meaning and 由 represents the sound.
Evolution

Bronze script
Mid Warring States (~300 BC)
Seal script
Shuowen (~100 AD)Regular script
ModernDefinitions
yóu
oil, fat, grease, lard; paints; oil; fat; grease; petroleum; to apply tung oil, paint or varnish; oily; greasy; glib; cunning
Sources