to speak openly and honestly about something
candour - honesty
If you speak with ‘candour’, you do so in a way that emphasizes truth over politeness or diplomacy. It does not mean to be rude, however. Instead it means to be bluntly honest with somebody, particularly about a subject that may be difficult or embarrassing to discuss. Can be used interchangeably with ‘candid.’
With surprising candour, my manager admitted that she had misjudged the situation and would take full responsibility.
When I asked my students to discuss their insecurities, their responses were remarkably candid.
I must speak candidly with you. I feel that you are wasting your talents because you are too afraid of failure to strive for something.