syn- /sin-/, sy- /si-/, syl- /sil-/, sym- /sim-/ or sys- /sis-/

Signifying together, with

• sharpshooting
• sharpshootings
• sharp-sighted
• sharp's the word
• sharp stick
• sharp-tailed grouse
• sharp-tongued
• sharp-toothed
• sharp-witted
• sharp-wittedly
• sharp-wittedness
• shash
• shashes
• shashlick
• shashlicks
• shashlik
• shashliks
• Shasta daisy
• shaster
• shasters
• shastra
• shastras
• shat
• shatoosh
• shatooshes