Synonyms for the phrase "lie in" include phrases such as "sleep late," "rest in bed," "stay in bed," and "lounge in bed." These phrases all express the idea of remaining in bed for an extended period of time, typically beyond one's usual wake-up time. Additionally, "lie in" can also be used to describe one's posture while in bed, as in "lie in a comfortable position." Other synonyms which describe this posture include "reclining," "resting," and "laying down." Overall, the phrase "lie in" and its synonyms all describe the act of remaining in bed for rest, relaxation, or leisure.