1.
reserve, hesitation, restraint
Holding back or being reserved in expressing one's true thoughts or opinions out of respect, fear, or social consideration. Almost always appears in the negative form 忌憚なく (without reserve).
忌憚 is almost exclusively used in the negative form to mean "without reserve" or "frankly."
Key expressions
Common collocations
Note: This is a formal expression commonly used in business and official contexts when inviting honest feedback or indicating one will speak candidly.