As a Verb or Adjective: 1. To think about something on and off for a long period of time. Idiomatic English = to have an idea or thought in the back of your mind. 2. To think that something is likely or is probably true. English = suspect. Interactive: 1. Used alone in response to being told something that you already thought or suspected was the case to mean "Oh, I thought as much!", "Oh, I suspected as much!".