Simple Definition of second thought
: a feeling of guilt, doubt, worry, etc., that you have after you have decided to do something or after something has happened
Full Definition of second thought
: reconsideration or a revised opinion of a previous often hurried decision <began to have second thoughts>
Examples of second thought
After she agreed to lend him the money, she had second thoughts.
She was having second thoughts about getting married.
He hardly gave it a second thought.
First Known Use of second thought
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