As a Noun: 1. A desire that someone has to know about things and to learn as much as possible about them. English = curiosity. As a Verb or Adjective: 1. To think about something you do not know or understand in order to try to guess or understand more about it. English = wonder. 2. Of a person, to have a desire to know about things and to learn as much as possible about them. English = (be) curious.