private parts; important parts
Euphemistic expression literally meaning 'important place'; used to refer to genitals or private areas in a polite or indirect way.
Teach small children, 'Cover your private parts.'
水着に着替えるときは、大事なところをタオルで隠す。
When changing into a swimsuit, cover your private parts with a towel.
Standard spelling using kana for ところ; the most common written form.
Kanji spelling for ところ; less common but still encountered.
Compound of 大事 (important) + な (attributive) + ところ (place). The euphemistic sense arises from referring to private parts as an 'important place' that should be protected or treated with care.