|on your toes
||I have to be on my toes in her class. I have to listen and think.
|on your way
||traveling, leaving, on the road home
||You can be on your way as soon as the tire is repaired.
||(See give it the once-over)
|once in a blue moon
||very seldom, rarely, in a long time
||"Have you heard from Paul?" "Once in a blue moon he calls,
maybe once a year."
|once upon a time
||a long time ago, at one time
||Once upon a time, there was a king named Arthur...
|one and the same
||the same as, not different, part and parcel
||Some people believe abortion and murder are one and the same thing.
|one at a time
||one then another, one by one
||Don't push, kids! It's one at a time.
|one born every minute
||many easy customers, lots of suckers
||"There's lots of suckers," he said. "There's one born every minute!"
|one brick short of a full load
||mentally slow, not all there
||I'm okay, but you may be one brick short of a full load. Ha ha.
|one by one
||one then another; one at a time, single file
||One by one the children entered the shelter.