This is the 8721st most frequent Japanese word.
智子
"智子" (Tomoko) is a Japanese female given name meaning "wise child" or "intelligent child."
Here, '智子' is used as a proper noun referring to a person's name, specifically 'Tomoko', followed by 'さん', which is an honorific suffix.
智子さんは優しい人です。
Tomoko is a kind person.
In this sentence, '智子' is used possessively with the particle 'の', indicating ownership or association as 'Tomoko's'.
私は智子の友達です。
I am a friend of Tomoko.
'智子' is the subject of the relative clause describing 'the picture that Tomoko painted', highlighting her action.