infrasonic /in-frə-sonˈik/ (acoustics)

1. (of frequencies) below the usual audible limit
2. Of, using or produced by infrasonic vibrations or pressure waves

inˈfrasound noun

• one-step
• one-stepped
• one-stepping
• one-steps
• one-stop
• one's true colours
• one-time
• one-to-one
• one-track
• one-trick pony
• one-two
• one-twos
• one-upmanship
• on every hand
• one-way
• one way and another
• one-way glass
• one-way mirror
• one way or the other
• one with another
• one-woman
• one-worlder
• one-worlders
• one-worldism
• oneyer