filipendulous (adj.)

*gwhī-, Proto-Indo-European root meaning "thread, tendon."

It forms all or part of: defile (n.) "narrow passage;" enfilade; filament; file (v.1) "place (papers) in consecutive order for future reference;" filigree; filipendulous; fillet; profile.

It is the hypothetical source of/evidence for its existence is provided by: Avestan jya- "bowstring;" Latin filum "a thread, string;" Armenian jil "sinew, string, line;" Lithuanian gysla "vein, sinew;" Old Church Slavonic zila "vein."

"hanging loosely or swinging freely from a fixed point above," c. 1600, from Latin pendulus "hanging down," figuratively "doubtful, uncertain, hesitating," from pendere "to hang" (from PIE root *(s)pen- "to draw, stretch, spin") + -ous. Related: Pendulously; pendulousness.