Surpassing; external; away from.
This prefix forms a great number of compounds—nouns, adjectives, verbs and adverbs—with a variety of senses. The most common one is that of surpassing or exceeding some norm—being more successful, enduring longer, and so on—frequently appearing in transitive verbs: outbid, outfight, outgrow, outlast, outperform, outshine, outstay. It forms nouns, adjectives, and adverbs describing a position or situation external to or separated from some place: outside, outdoors, outfield, outbuilding, outpost, outpatient, outcast. It can suggest movement away from some location or position: outwards, outbound; this can often be figurative in sense: outcry, outgoing, outgrowth, outpouring, output.