Proto-Indo-European root meaning "to wind, turn."
It forms all or part of: anastrophe; antistrophe; apostrophe (n.1); apostrophe (n.2); boustrophedon; catastrophe; epistrophe; strabismus; strap; strep; strepto-; streptococcus; streptomycin; strobe; strobic; stroboscope; strop; strophe; strophic.
It is the hypothetical source of/evidence for its existence is provided by: Greek strophe "stanza," originally "a turning," strephein "to turn," strophaligs "whirl, whirlwind," streblos "twisted," stremma "that which is twisted."
streaking
streaky
stream
streamer
streamline
*streb(h)-
street
street-car
street-walker
street-wise
strength