infrasonic /in-frə-sonˈik/ (acoustics)

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

• ottrelite
• ottrelites
• ottrelite-slate
• ou
• OU
• ouabain
• ouabains
• ouakari
• ouakaris
• ouananiche
• pterylographical
• pterylographically
• pterylographies
• pterylography
• pteryloses
• pterylosis
• PTFE
• ptiloses
• ptilosis
• ptisan
• ptisans
• PTO
• ptochocracies
• ptochocracy
• Ptolemaean