The word "吃腻" is formed by combining the character "吃" (chī), meaning "to eat", with the character "腻" (nì), meaning "greasy" or "tired of". The first character denotes the action of eating, while the second character describes the resultant state of being fed up or disgusted due to overconsumption. Together, they create a compound word where the meaning is derived from the sequence: the action leads to the state, specifically indicating that someone has eaten something to the point of no longer wanting it.