Alternative form of of

A blood type that has no antigens. It lacks the A, B and Rh factors on the blood cells. It is the universal donor for blood and can give blood to any blood type, but can only receive O- blood.

(organic chemistry) ortho-

A colloquializing suffix, typically appended to names, abbreviations of long words, or substantive uses of adjectives.

(humorous) Converts certain words to faux Italian or Spanish. Can be used with Spanish el for expressions such as el stinko.

Added to verb stems to create a noun describing an error relating to the action described by the verb.

(unstressed) Contraction of of.. / (obsolete, unstressed) Contraction of on.

descendant of; used to form Irish patronymic surnames.

The fifteenth letter of the English alphabet, called o and written in the Latin script.

Something shaped like the letter O.