Former, or single occasion

adjective

1. Former, sometime

   "a onetime actor"

2. Occurring only once one-shot

adverb

1. Formerly

noun

1. A shot (as in hockey or soccer) that is made by immediately striking a moving puck or ball (as when receiving a pass from a teammate) without first stopping and controlling it

idiom

1. During one particular moment

   "I can only do one thing at a time."

2. During one period of time without stopping

   "She can sit and read for hours at a time."

idiom

1. During one period of time in the past

   "At one time there was only one grocery store in town."

idiom

1. Not very often, but occasionally

   "We all do foolish things at one time or another."

idiom

1. Again once more

   "Would you please do it one more time?"

idiom

1. To deal with each day's problems as they come instead of worrying about the future

   "It's important to take things one day at a time so you don't feel too overwhelmed."

idiom

1. To deal with each day's problems as they come instead of worrying about the future

   "Take one day at a time and don't expect things to change overnight."