Definition of square one
: the initial stage or starting point <the failure set us back to square one>
Examples of square one in a sentence
They lost everything and found themselves back at square one.
Origin and Etymology of square one
from the use of numbered squares in some board games
First Known Use: 1960
SQUARE ONE Defined for English Language Learners
Definition of square one for English Language Learners
: the beginning stage or starting point
Seen and Heard
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