Sekirov Dictionary

guard one's tongue

verb1

•
To be careful in what one says; to avoid divulging information or speaking in a way considered to be inappropriate or offensive.
- […] of course it is a little out of character to call upon me to guard my tongue, when it is the privilege of a freeman to speak his mind […] — 1793

forms

guarded one's tongue · guarding one's tongue · guards one's tongue

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