"girl-like," 1866, from girl + -y (2). Reduplicated form girly-girly (adj.) is recorded from 1883; as a noun from 1882.
girly (n.)
"little girl," 1839, girlie; 1824, gurlie (in Scottish dialect), from girl + -y (3). Early uses in all spellings suggest it was regarded as a Scottish word. Another diminutive was girleen (1836) with an Irish ending.
girl
girlfriend
girlhood
girlie
girlish
girly
Girondist
girt
girth
gist
git