section of a circle

(Geometry) segment of a circle

quadrant, a quarter of a circle or circular body

revolutionist

change, alteration, turn

Circumcentre.

agricultural revolution

declaration, proclamation of revolution

circles, limits, ranges

circle, ring, orbit

semi-circle, a half of a circle or of its circumference

the sphere (of activity, etc.) to reduce

affliction caused by maintaining formalities, fabrication

(Historical) tenure by which houses or lands are held of the king or other lord of a borough or city; at a certain yearly rent, or by services relating to trade or handicraft

a measuring unit used for measuring length (equivalent to about a yard)

poet of revolution, revolutionary poet, a poet who instigates revolution through his poetry

flag of revolution

start of winter in the northern hemisphere