Is the word 'breast' okay to use in formal conversation? I know some slangs for it

Breast is okay to use in a formal conversation but if you still think it is uncomfortable for you to say it or you think that the other person will feel embarrassed then you can use the word 'chest'. Breast is usually only used for female but 'chest' can be used for both female and male.|it is more formal but chest would be better in that situation as it would make people uncomfortable if you said breast out loud
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