We found 4 dictionaries that define the word third planet:

General (2 matching dictionaries)

1. Third planet: Wikipedia, the Free Encyclopedia
2. Third Planet: Wiktionary

Computing (1 matching dictionary)

3. Third Planet: Encyclopedia

Medicine (1 matching dictionary)

4. Third Planet: Medical dictionary

Definitions from Wiktionary (Third Planet) ▸ noun:  The planet Earth. Phrases: third planet from the sun, The Mystery of the Third Planet, more... ▸ Words similar to third planet ▸ Usage examples for third planet ▸ Idioms related to third planet ▸ Wikipedia articles (New!) ▸ Words that often appear near third planet ▸ Rhymes of third planet ▸ Invented words related to third planet