Oncer

//ˈwʌnsɚ// noun, slang

noun, slang ·Moderate ·College level

Definitions

Noun
  1. 1
    A one-pound note. historical, informal

    "On whatever point Jane’s eyes rested, through whichever line her gaze ran, she saw cheques being signed, credit-card counterfoils being scrawled across, standing orders being arranged, and cash – wholesome dosh, ponies, monkies, oncers, coins of the realm – flowing around like mercury, like some element."

  2. 2
    A fan of the television series Once Upon a Time. slang

    "And fun because, well, he gets to interact with “Oncers” at fan events like PaleyFest and Comic Con […]"

  3. 3
    A person who does something once. poetic

    "Could he but once see Nature as / In truth she is for ever, / What oncer would not fall in love?"

  4. 4
    A single sexual encounter between two individuals, a one-night stand. informal
  5. 5
    A person with whom one shares a single sexual encounter, a one-night stand. informal

Example

More examples

"On whatever point Jane’s eyes rested, through whichever line her gaze ran, she saw cheques being signed, credit-card counterfoils being scrawled across, standing orders being arranged, and cash – wholesome dosh, ponies, monkies, oncers, coins of the realm – flowing around like mercury, like some element."

Etymology

Etymology 1

From once + -er (relational suffix) or + -er (occupational suffix).

Etymology 2

From once + -er.

Related phrases

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.