(adv., prep., n., adj. & interj.) The word 'over' has a mouthful of meanings.
(adv.) Often used as 'over and over (again)/over again', this definition means repeatedly and happening again and again; from the beginning. Using it in a sentence:
He played the song over and over again, until I got tired. (He played the song repeatedly until I got tired.)
"We're starting over," exclaimed Joan. ("We're starting from the beginning," said Joan.)
(prep.) This definition of the word means 'above', to a higher extent. This would be best explained with a picture, so here is one for you. Using it in a sentence:
The balloons are floating over the trees. (The balloons are floating above the trees.)
The water was over my knees. (The water level was above the level of my knees.)
(prep.) More/greater than, >. Using it in a sentence:
He earned over a thousand pounds! (He earned more than a thousand pounds [1001 or more]!)
The village is over 45 kilometres away; how are you going to get there so quickly? (The village is more than 45km from here, how are you going to get there so quickly?)
More definitions coming soon!