na-adjective, noun
Describes a formal, respectful, and sometimes overly polite manner. Often used in social or business contexts where decorum is emphasized.
彼は慇懃な態度で客を迎えた。
He greeted the guests with a courteous manner.
慇懃無礼な言い方に腹が立った。
I was annoyed by his politely rude way of speaking.
noun, na-adjective
Refers to a close, often affectionate relationship; can imply sexual intimacy. This sense is somewhat literary and less common in everyday speech.
二人は長年の慇懃な関係にある。
The two have had an intimate relationship for many years.
The word is composed of two kanji meaning 'courteous' and 'sincere', reflecting its original sense of heartfelt politeness. The extended meaning of intimacy likely developed from the idea of close, sincere relations.