*syu- sy?-, also s?:-, Proto-Indo-European root meaning "to bind, sew." It forms all or part of: accouter; couture; hymen; Kama Sutra; seam; sew; souter; souvlaki; sutra; sutile; suture. It is the hypothetical source of/evidence for its existence is provided by: Sanskrit sivyati "sews," sutram "thread, string;" Greek hymen "thin skin, membrane," hymnos "song;" Latin suere "to sew, sew together;" Old Church Slavonic šijo "to sew," šivu "seam;" Lettish siuviu, siuti "to sew," siuvikis "tailor;" Russian švec "tailor;" Old English siwian "to stitch, sew, mend, patch, knit together."

Sources:

• A Dictionary of Selected Synonyms in the Principal Indo-European Languages, University of Chicago (By: Carl Darling Buck) 1988.
• Etymological Dictionary of Latin and the other Italic Languages (By: Michiel de Vaan) 2008.
• The American Heritage Dictionary of Indo-European Roots (By: Calvert Watkins) 2000.
• Noun Declension in Indo-European (Sindhueuropaia Deklination Nomnes) By: Carlos Quiles.
• Online Etymology Dictionary (By: Douglas Harper)