Or

A termination of Latin nouns, denoting an agent, as in actor, creditor. It is annexed to many words of English origin, as in lessor. In general, or is annexed to words of Latin, and er to those of English, origin. See Er.

conj. [Contracted from A-S. ādher, ādhør, for āwdher, āwdhor, ahwādhher, one of two, either, other; O. Eng. outher, other, other, aythere, e. g., “Tell us by what auctoritie thou doest these thynges. Other who is he that gave the thys auctorite?” Tyndale’s New Testament. O. Fries. auder, uder, L. Ger. adder, oer, O. H. Ger. odar, odir, N. H. Ger. oder, L. Ger. edder, eer, Icel. edha, eda, A-S. edhdha, edha, oddhe, O. H. Ger. edho, etho, eddo, edo, edh, ed, Goth. aiththau, O. Sax. efthō, eftha, O. Fries. efther, oftha, ofte, oft, O. D. ofte, N. D. of, O. H. Ger. alda, alde, olde, Icel. ella, Sw. & Dan. eller.] A connective that marks an alternative; as, you may read or may write,—that is, you may do one of the things at your pleasure, but not both. It corresponds to either. You may ride either to London or to Windsor. It often connects a series of words or propositions, presenting a choice of either; as, he may study law, or medicine, or divinity, or he may enter into trade.

Or sometimes begins a sentence; but in this case it expresses an alternative with the foregoing sentence. “Or what man is there of you, whom if his son ask bread, will he give him a stone?” Matt. vii. 9. In poetry, or is sometimes used for either.

For thy vast bounties are so numberless, That them or to conceal or else to tell Is equally impossible. Cowley.

He stands not still, but or decays or grows Into a boundless blessing. Byron.

Or is often used to express an alternative of terms, definitions, or explanations of the same thing in different words; as, a certain figure is a square, or a figure under four equal sides and angles.

adv. [A-S. ǽr, ere, before. See ERE.] Ere; before; sooner than. [Obs.]

He was of Lindesay, als I ore told. R. Brunne.

But natheless, while I have time and space, Or that I further in this tale pace. Chaucer.

Or ever, sooner than ever; before ever. “I was set up from everlasting, from the beginning, or ever the earth was.” Prov. viii. 23.