Oscillate/ˈɑːsɪleɪt/ Definition 1 of 3Pro Tip 1/3Physical Movement Used when describing something with a motion similar to a swinging pendulum. The tree branches oscillated in the wind. Pro Tip 2/3Metaphorical Use Sometimes used metaphorically for things that don't physically swing but vary regularly. The discussions oscillated between serious and humorous. Pro Tip 3/3Repetitive Action Emphasizes the regular back-and-forth characteristic of an action or process. Share prices oscillated throughout the trading day.