순진무구가 · 순진무구를
pure and innocent, without a trace of guile
Example
아이의 순진무구한 웃음에 마음이 따뜻해졌어요.
The child's pure, innocent smile warmed my heart.
Word parts
순 pure+진 true+무 without+구 stain
Literally 'pure and genuine, without stain'.
Good to know
Most often as an adjective: 순진무구하다, 순진무구한 눈빛.