com·pet·i·tor 
(kəm-pĕtĭ-tər)
(kəm-pĕtĭ-tər)n.
One that competes with another, as in sports or business; a rival.
- petrogenesis
- petrogenetic
- petroglyph
- petroglyphic
- Petrograd
- petrographer
- petrographic
- petrographical
- petrographically
- petrography
- petrol
- petrolatum
- petroleum
- petroleum coke
- petroleum ether
- petroleum jelly
- petrolic
- petrologic
- petrological
- petrologically
- petrologist
- petrology
- Petronius
- "Petronius Arbiter."
- Petropavlovsk-Kamchatski