bullet

noun

1. a small ball or cone-shaped missile of lead, metal alloy, etc., to be shot from a firearm
2. loosely a bullet in its casing; cartridge
3. anything like a bullet in shape, action, etc.
4. a solid dot used as at the beginning of a line for emphasis
5. ☆ a bullet-shaped symbol used to indicate a rapid increase in sales and airplay of musical recordings, videos, etc.