Bicentennial
two hundred years
quadrant
a quarter (1/4) of a circle, or an of the 4 parts of an area divided by two perpendicular lines
Quartet
a group of 4 , especially musicians
Centigrade
A measurement of temperature where water freezes at 0 degrees and boils at 100 degrees.
trilogy
a group of 3 literary or musical works with a related theme
Deci
ten
triumverate
a group of 3 people in a position of power or authority
decimate
to wipe out or kill off (originally meaning to kill 1 out of 10, or 10%)
centenary
a 100-year period
trisect
to divide into 3 parts
Bi
two
Quad
four
Tri / Tres
three
quatrain
a group of 4 lines of poetry
uni
one
Centi
one hundred
Duo/Dou/Du
two
decathlon
an athletic contest in which each contestant competes in 10 events