bestest

[ bes-tist ]
/ ˈbɛs tɪst /

adjective Informal.

very best; better than the best: She's my bestest friend in the whole world.

Origin of bestest

1750–60; best + -est1 suffix forming the superlative
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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