sty·lus 
(stīləs)
(stīləs)n. pl. sty·lus·es or sty·li (-lī)
1. A sharp, pointed instrument used for writing, marking, or engraving.
2. Computers A pointed instrument used as an input device on a pressure-sensitive screen.
3. A phonograph needle.
4. A sharp, pointed tool used for cutting the jagged grooves that record sound on a phonograph record.
[Latin, alteration (influenced by Greek stūlos, pillar) of stilus.]
stylus