στρεβλός

Etymology
Maybe from, the same root of. However, due to the irregular correspondence of β with φ  and the connection with words like  and, Beekes suggests a  origin.

Adjective

 * 1) twisted, crooked, awry
 * 2) knit, wrinkled (of the brows)
 * 3) crooked, cunning
 * 4) perverse, froward