plan·e·tol·o·gy 
(plăn′ĭ-tŏlə-jē)
(plăn′ĭ-tŏlə-jē)n.
The branch of astronomy that deals with the composition and structure of the planets of the solar system and with the relationships, similarities, and differences between them.
plan′e·to·logi·cal (plăn′ĭ-tl-ŏjĭ-kəl) adj.
plan′e·tolo·gist n.
- brit
- Brit
- Brit.
- Britain
- Britannia
- britannia metal
- Britannic
- britches
- Briticism
- British
- British America
- British America
- British angora
- British Antarctic Territory
- British anti-lewisite
- British Cameroons
- British Columbia
- British Commonwealth
- British Commonwealth
- British East Africa
- British Empire
- British English
- Britisher
- British Guiana
- British Guiana