or

Etymology 1

From Middle English or; partially contracted from other, auther, from Old English āþor, āwþer, āhwæþer ("some, any, either"; > either); and partially from Middle English oththe, from Old English oþþe, from Proto-Germanic *efþau (“or”).

conj

1. Connects at least two alternative words, phrases, clauses, sentences, etc., each of which could make a passage true.
   In Ohio, anyone under the age of 18 who wants a tattoo or body piercing needs the consent of a parent or guardian.
   He might get cancer, or be hit by a bus, or God knows what.
2. (logic) An operator denoting the disjunction of two propositions or truth values. There are two forms, the inclusive or and the exclusive or.
3. Counts the elements before and after as two possibilities.
4. Otherwise (a consequence of the condition that the previous is false).
   It's raining! Come inside or you'll catch a cold!
5. Connects two equivalent names.
   The country Myanmar, or Burma

Etymology 2

From Etymology 1 (sense 2 above).

noun

1. (logic, electronics) Alternative form of OR

Etymology 3

Borrowed from Middle French or (“yellow”), from Old French or, from Latin aurum (“gold”). Doublet of aurum.

noun

1. (heraldry) The gold or yellow tincture on a coat of arms.
   The metals are gold and silver, these being termed "or" and "argent". 1909, Arthur Charles Fox-Davies, A Complete Guide to Heraldry
   In engraving, "Or" is expressed by dots. 1889, Charles Norton Elvin, A Dictionary of Heraldry
   or:

adj

1. (heraldry) Of gold or yellow tincture on a coat of arms.

Etymology 4

Late Old English ār, from Old Norse ár. Compare ere.

adv

1. (obsolete) Early (on).
2. (obsolete) Earlier, previously.

prep

1. (now archaic or dialect) Before; ere. Followed by "ever" or "ere".
   I looked to heaven, and tried to pray; But or ever a prayer had gusht, A wicked whisper came, and made My heart as dry as dust. 1834, Samuel Taylor Coleridge, The Rime of the Ancient Mariner