# expectation

Pronunciation: say "ek-spek-TAY-shuhn" US/UK /ˌɛk.spɛkˈteɪ.ʃən/, AUS /ˌek.spekˈtæɪ.ʃən/

## Noun

1. Whatever someone expects or looks for in a given situation.
   - Simple: The thing you think will happen, or what you hope to get.
   - _The job fell short of his expectation of steady, meaningful work._
   - _Reality rarely matches the expectations we build up beforehand._
2. Anticipation of an event that one believes will soon take place, or the act of awaiting it.
   - Simple: The feeling of waiting for something you believe will soon happen.
   - _She opened the letter with breathless expectation._
   - _Months of expectation ended the moment the train finally arrived._
3. An unstated obligation or duty that one person believes another is bound to fulfill.
   - Simple: A duty you quietly believe someone else should do for you, even if no one says it.
   - _The role carried an expectation of constant availability that no contract mentioned._
   - _Cultural expectations often shape how children treat their aging parents._
4. The prospect of good things to come, especially the likelihood of inheriting property or gaining rank.
   - Simple: A good chance of getting something fine later on, like money or a high rank.
   - _With no expectation of land or title, he set out to make his own way._
   - _The family's expectations rested entirely on a distant relative's will._
5. The long-run average value of a variable over many independent repetitions of an experiment.
   - Simple: The long-run average value you would get by repeating something many times.
   - _Engineers computed the expectation of the signal to predict its average strength._
   - _For a fair coin scored one or zero, the expectation equals one half._
6. The value of a chance (such as the prospect of a prize or property) that depends on some uncertain future event.
   - Simple: The worth of a chance to win something, based on an event that may or may not happen.
   - _An insurer prices each policy by estimating the expectation attached to an uncertain loss._
   - _The heir's expectation depended wholly on whether the childless lord died without a will._
7. The arithmetic mean of a set of values. *(colloquial)*
   - Simple: The average of some numbers, found by adding them and dividing by how many there are.
   - _She reported the expectation of the daily temperatures across the month._
   - _The analyst quoted the expectation of the sample rather than its median._

## Noun

8. The practice of leaving a disease largely to the healing efforts of nature rather than active treatment. *(rare)*
   - Simple: Letting an illness get better on its own, trusting the body instead of using treatment.
   - _The physician chose expectation over bleeding the patient, trusting nature to mend the fever._
   - _Treatment then leaned heavily on expectation, with rest and time doing most of the work._

## Origin

This word came through Middle French "expectation" from Latin "exspectātiō," based on "exspectō" ("expect"); by surface analysis it is "expect" plus "-ation." It displaced the native Old English "wēn."

Source: DictionaryAI, https://dictionaryai.com/define/expectation (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).