Single occasion

adverb

1. One time and no more

   "rode a horse only once"

2. At any one time under any circumstances ever

   "didn't once thank me"

3. At some indefinite time in the past formerly

   "was once a booming mining town"

4. By one degree of relationship

   "first cousin once removed"

noun

1. One single time one time at least

   "Please be on time this once."

adjective

1. That once was former

   "… contributions to enrich the legal resources of the once province of Britain."

conjunction

1. At the moment when as soon as

   "Once she spoke, I recognized her."

conjunction

1. Once

noun

1. A swift examination or survey

idiom

1. Used to mean that a person who has failed or been hurt when trying to do something is careful or fearful about doing it again

idiom

1. Very rarely

   "It happens once in a blue moon."

idiom

1. Very rare or very rarely

   "a once-in-a-lifetime opportunity"

idiom

1. One or two times a very few times

   "We've eaten at that restaurant once or twice."

noun

1. The one, particular, or present occasion, purpose, or use

   "for the nonce"

2. The time being

adjective

1. Occurring, used, or made only once or for a special occasion

   "a nonce word"

idiom

1. For now for the moment

   "The team is called "the Lions," at least for the nonce."