center i.e. center of a circle
centre i.e. shopping centre
Gentlemen, this is a motorcycle forum, NOT a University course.
That said (from the Oxford English Dictionary website):
Definition of centre
1 the point that is equally distant from every point on the circumference of a circle or sphere.
a point or part that is equally distant from all sides, ends, or surfaces of something:
the centre of the ceiling
the city centre
a political party or group whose opinions avoid extremes:
[as modifier]:
a new centre party
the middle player in a line or group in certain team games.
a kick, hit, or throw of the ball from the side to the middle of field in soccer, hockey, and other team games.
the filling in a chocolate:
truffles with liqueur centres
a pivot or axis of rotation.
a conical adjustable support for a workpiece in a lathe or similar machine.
2 the point from which an activity or process is directed, or on which it is focused:
the city was a centre of discontent
the managing director is at the centre of a row over policy
the most important place in the respect specified:
Geneva was then the centre of the banking world
3 a place or group of buildings where a specified activity is concentrated:
a conference centre
Now back to the Moto Speak...