1
general::
Phrase(s): cotton (on)to someone or something
Rur. to begin to like or agree to someone or something quickly. • She began to cotton to Fred, despite his country ways. • She cottoned onto Jane’s way of thinking.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
1. Take a liking to, get along with, as in This dog doesn't cotton to strangers. Although this verbal phrase comes from the noun for the fabric, the semantic connection between these parts of speech is unclear. [Early 1800s] 2. Also, cotton on to. Come to understand, grasp, as in She didn't really cotton on to what I was saying. [Colloquial; early 1900s]
American Heritage Idioms