1. Growing or remaining under water
   "viewing subaqueous fauna from a glass-bottomed boat"
   - subaquatic, submerged, submersed, underwater

See also: aquatic

• single-propeller plane
• single-reed instrument
• single-reed woodwind
• single-rotor helicopter
• single-seeded
• single-sex
• single-shelled
• single-spaced
• single-spacing
• single-stranded
• single-valued function
• singleness
• singles
• singlestick
• singlet
• singletary pea
• singleton
• singletree
• Singlish
• singly
• singsong
• swaddle
• swaddling bands
• swaddling clothes
• swag