Collocation refers to the appearance or occurrence of groups or pairs of words, particularly when more frequent than random chance would suggest.

Wikipedia defines collocation this way: In corpus linguistics, a collocation is a sequence of words or terms that co-occur more often than would be expected by chance. Chance does not mean pure randomness or arbitrariness; in this sense refers to the preference for certain words being more commonly paired than other choices which have the same meaning.

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