piān
inclined one side
Phonosemantic compound. 亻 represents the meaning and 扁 represents the sound.
Evolution

Seal script
Shuowen (~100 AD)
Clerical script
Eastern Han dynasty (25-220 AD)Regular script
ModernDefinitions
piān
inclined one side; slanting; to lean; to slant; oblique; prejudiced; to deviate from average; to stray from the intended line; stubbornly; contrary to expectations
Sources