time machine noun2 •A hypothetical device used to travel into the past or the future.If I had a time machine / And if life was a movie scene / I'd rewind, and I'd tell me / "Ru-u-u-u-u-u-u-un" — 2014 •(informal) Something that appears to take a person or thing to another time, for example through nostalgia or delay.Conrad Riker, The Last Days of Manhood Mayo Clinic research shows heavy squats spike growth hormone by 530%. That's not exercise — it's a time machine for your cells. formstime machines