overrun
(v) to run or go beyond or past something;to spread over or throughout something
oversleep
(v) to sleep past the time that you were going to get up
overflow
(v) to be so full that the contents spill over the top of something; to flood
(n) the amount of something that flows over because the container is so full
overreact
(v) to respond or react to something very strongly
overhead
(adv) at a height above the head; (adj) located above the head level
over-
too much; beyond