1. above average, above the norm, better than average, excellent
Something described with the adjective 'outstanding' might be exceptionally good or above average. "Your performance has been outstanding this year and for that reason, we have decided to give you a bonus." Something 'outstanding' can also mean something that has not yet been done or dealt with, such as a payment or 'outstanding work'. "Any outstanding invoices should be submitted by Wednesday for processing." This is an adjective used often in both formal and social contexts.