We found 15 dictionaries that define the word glacial period:

General (12 matching dictionaries)

1. glacial period: Merriam-Webster
2. glacial period: Oxford Learner's Dictionaries
3. glacial period: Collins English Dictionary
4. glacial period: Vocabulary.com
5. glacial period: Cambridge Advanced Learner's Dictionary
6. glacial period: Dictionary.com
7. Glacial period: Wikipedia, the Free Encyclopedia
8. glacial period: Rhymezone
9. glacial period: FreeDictionary.org
10. glacial period: Mnemonic Dictionary
11. glacial period: TheFreeDictionary.com
12. glacial period: Wiktionary

Computing (1 matching dictionary)

13. glacial period: Encyclopedia

Tech (2 matching dictionaries)

14. Glossary of Meteorology (No longer online)
15. Lake and Water Word Glossary (No longer online)

(Note: See glacial_periods as well.)

Definitions from Wiktionary (glacial period) ▸ noun:  An interval of time within an ice age that is marked by colder temperatures and glacier advances. Phrases: Last Glacial Period, Penultimate Glacial Period, more... ▸ Words similar to glacial period ▸ Usage examples for glacial period ▸ Idioms related to glacial period ▸ Wikipedia articles (New!) ▸ Words that often appear near glacial period ▸ Rhymes of glacial period ▸ Invented words related to glacial period