"full of bends or curves, winding, sinuous," c. 1600, from Latin flexuosus, from flexus (n.) "a bending," from flectere "to bend" (see flexible). From 1620s as "undulating."
the flexuous bed of the stream
flexible
flexion
flexography
flexor
flextime
flexuous
flexure
flibbertigibbet
flick
flicker
flier