1. (physics) sound waves having frequency below the human audible range (below about 20 Hz)

Encyclopedia: Infrasound

• CBR
• CBS
• cc
• ccc
• CCD
• CCRC
• CCS
• CCTV
• cd
• CD burner
• birch tree
• birchbark
• birchbark canoe
• birchen
• bird
• bird cherry
• bird cherry tree
• bird dog
• bird family
• bird fancier
• bird feed
• bird flu
• bird food
• bird genus
• bird louse