Bound morpheme

In morphology, a bound morpheme is a morpheme that appears only as part of a larger word; a free morpheme or unbound morpheme is one that can be used stand alone or can appear with other lexemes. A bound morpheme is also known as a bound form, and similarly a free morpheme is a free form.

Many roots are free morphemes, e.g., ship- in "shipment", while others are bound. Roots normally carry lexical meaning. Words like chairman that contain two free morphemes (chair and man) are referred to as compound words.

Affixes are always bound in English, although languages such as Arabic have forms which sometimes affix to words and sometimes can stand alone. English language affixes are almost exclusively prefixes or suffixes. E.g., pre- in "prefix" and -ment in "shipment". Affixes may be inflectional, indicating how a certain word relates to other words in a larger phrase, or derivational, changing either the part of speech or the actual meaning of a word.

Cranberry morphemes are a special form of bound morphemes where the bound morpheme does not have an independent meaning, only serving to distinguish one word from another, as in cranberry, where the free morpheme berry is preceded by the bound morpheme cran-, which does not have independent meaning.

Words can be formed purely from bound morphemes, as in English permit, ultimately from Latin per "through" + mittō "I send", where per- and -mit are bound morphemes in English. However, these are often instead analyzed synchronically as simply a single morpheme.

A similar example is given in Chinese, where most morphemes are monosyllabic and identified with a Chinese character due to the largely morphosyllabic script, but disyllabic words exist that cannot be analyzed into independent morphemes, such as 蝴蝶 húdié 'butterfly'. In this case the individual syllables and corresponding characters are only used in this word, and while they can be interpreted as bound morphemes 蝴 hú- and 蝶 -dié, this is more commonly considered a single disyllabic morpheme. See polysyllabic Chinese morphemes for further discussion.

Linguists usually distinguish between productive and unproductive forms when speaking about morphemes. For example, the morpheme ten- in tenant was originally derived from the Latin word tenere, "to hold", and the same basic meaning is seen in such words as "tenable" and "intention." But as ten- cannot be used in English to form new words, most linguists would not consider it to be a morpheme at all.

See also

• Fixed expression
• Fossil word
• Unpaired word