无理

irrational / unreasonable

not to have / no / none / not / to lack / un- / -less

texture / grain (of wood) / inner essence / intrinsic order / reason / logic / truth / science / natural science (esp. physics) / to manage / to pay attention to / to run (affairs) / to handle / to put in order / to tidy up

to make trouble without reason (idiom); to be deliberately provocative

irrational number

rude and unreasonable