"spacing" - key terms from Wikipedia

bore spacing
bus stop spacing
carrier spacing
channel spacing
character spacing
closer spacing
cylinder bore spacing
even spacing
gate spacing
ghz spacing
hand spacing
letter spacing
line spacing
microsecond spacing
pin spacing
proportional spacing
repeater spacing
repetition spacing
spacing
spacing	effect
spacing	guild
spacing	of their children
spacing	typically
third spacing
train spacing
transom spacing
word spacing