Changes to Old English vocabulary

Many words that existed in Old English did not survive into Modern English. There are also many words in Modern English that bear little or no resemblance in meaning to their Old English etymons. Some linguists estimate that as much as 80 percent of the lexicon of Old English was lost by the end of the Middle English period, including a large number of words formed by compounding, e.g. bōchūs ('bookhouse', 'library'), yet we still retain the component parts 'book' and 'house'. Certain categories of words seem to have been especially vulnerable. Nearly all words relating to sexual intercourse and sexual organs were supplanted by words of Latin or Ancient Greek origin. Many, if not most, of the words in Modern English that are used in polite conversation to describe body parts and bodily functions are of Latin or Greek origin. The words which were used in Old English for these same purposes are now mostly either extinct or considered crude or vulgar, such as .

Some words became extinct while other near-synonyms of Old English origin replaced them ('limb' survives, yet lið is gone or survives dialectally as ). Many of these linguistic changes were brought on by the introduction of Old Norse and Norman French words, while others fell away due to the natural processes of language evolution.

Modern English has no Germanic words left that mean 'animal' in its most generic sense of 'non-human creature'. Old English dēor, gesceaft, gesceap, nēat and iht were all eclipsed by 'animal', 'beast', 'creature' and 'critter', all of which are of Latin origin.

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