O'er is a poetic contraction of the word over. It's typically found in old poetry and song lyrics. O'er is a contraction, meaning it's a shortened form of a word in which certain letters are replaced with an apostrophe. We use contractions all the time, especially to combine two words into one, as in it's and isn't.

What is the meaning of O er Vales?

adv a poetic contraction of → over.

What is o'er an example of?

A contraction, generally a poetical contraction, of over.