Entrenchment

Entrenchment is a process that leads to increased strengthening of a form-function relation or cue over time. Examples of relevant linguistic forms include phonemes, words, phrases, and constructions. With repeated successful use, a form becomes stronger and can resist competitors. Error decreases, reaction times speed up, and fluency increases. Once entrenched, it is difficult to unlearn a form and difficult to learn new ways of marking the relevant underlying functions. (Brian MacWhinney)