Simple Definition of mastodon

from our Learner's Dictionary

mastodon

noun

ˈmæstəˌdɑːn How to pronounce mastodon (audio)
plural mastodons
: a type of animal that was related to the mammoth and that lived in ancient times

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“Mastodon.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/mastodon. Accessed 24 Jun. 2026.

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