1. Too small to be seen without an ultramicroscope

See also: ultramicroscope

• spare-time activity
• sparely
• spareness
• sparer
• sparerib
• spareribs
• Sparganiaceae
• Sparganium
• sparge
• sparge pipe
• sparger
• sparid
• sparid fish
• yclept
• yd
• yds
• ye
• yea
• yeah
• yean
• yeanling
• year
• year dot
• year of grace
• year of our Lord