Definition of Morphemes

As scientists have studied the composition of the universe, they've determined that the smallest unit for measuring an element is the atom. If you think of the periodic table of elements, atoms are what comprise elements, such as hydrogen, carbon, silver, gold, calcium, and so on. Scientists utilize this classification system for uniformity, so that they're on the same page in the terminology of their studies.
Similarly, linguists, or those who study language, have devised a category for the smallest unit of grammar: morphemes. Morphemes function as the foundation of language and syntax. Syntax is the arrangement of words and sentences to create meaning. We shouldn't confuse morphemes as only a given word, number of syllables, or only as a prefix or suffix. The term morpheme can apply to a variety of different situations. Let's take a look!

Types of Morphemes

In linguistics, we would further classify morphemes as either as phonemes (the smallest units of grammar recognizable by sound) or graphemes (the smallest units of written language). For our purposes, we will focus on graphemes.
Let's examine the word nonperishable, analyze it, and then discuss terms associated with it.
Nonperishable is comprised of three morphemes: non-, perish, and -able. It actually has five syllables though, which is a good example of why morphemes and syllables are not synonymous.

• non- is an example of a prefix, or a morpheme that precedes a base morpheme
• perish is an example of a base morpheme, as it gives the word its essential meaning
• -able is an example of a suffix, or a morpheme that follows a base morpheme

Both non- and -able are examples of an affix, a morpheme attached prior to or following a base that cannot function independently as a word.
We can also take a look at this chart to see some examples of how morphemes work:

A Morpheme as a Word

When we can take a morpheme independently and use it as a stand-alone word in a sentence, it is known as a base. As the chart indicated, these can be nouns, verbs, adjectives, conjunctions, prepositions, or determiners. We also classify a morpheme that can function as a stand-alone word as free.
In the sentence:
The bird-like man hardly touched his food at dinner.
There are a total of twelve morphemes, and ten of the twelve are free:

• the (article)
• bird (noun)
• like (adjective)
• man (noun)
• hard (adjective)
• touch (verb)
• his (determiner)
• food (noun)
• at (preposition)
• dinner (noun)

The other two morphemes, -ed and -ly, are types of affixes, which brings us to our next topic.

A Morpheme as an Affix

An affix is a bound morpheme, which means that it is exclusively attached to a free morpheme for meaning. Prefixes and suffixes are the most common examples.

• Common prefixes are : re-, sub-, trans-, in-, en-, ad-, dis-, con-, com-
• Common suffixes are: -s, -es, -able, -ance, -ity, -less, -ly, -tion

It is also important to note two types of affixes: inflectional and derivational.
Inflectional morphemes can only be a suffix, and they transform the function of a word, such as adding an -ly suffix to the base noun of friend.This becomes the word friendly, which has two morphemes. The -ly is an inflectional morpheme because it changes the noun into an adjective.
Derivational morphemes can be either a suffix or a prefix, and they have the ability to transform either the function or the meaning of a word. An example would be adding the suffix -less to the noun meaning. The suffix then makes the word the opposite of itself, thus drastically changing meaning.

Examples (English)

Unladylike The word unladylike consists of three morphemes and four syllables. Morpheme breaks: un- 'not' lady '(well behaved) female adult human' -like 'having the characteristics of' None of these morphemes can be broken up any more without losing all sense of meaning. Lady cannot be broken up into "la" and "dy," even though "la" and "dy" are separate syllables. Note that each syllable has no meaning on its own. Dogs The word dogs consists of two morphemes and one syllable: dog, and -s, a plural marker on nouns Note that a morpheme like "-s" can just be a single phoneme and does not have to be a whole syllable. Technique The word technique consists of only one morpheme having two syllables. Even though the word has two syllables, it is a single morpheme because it cannot be broken down into smaller meaningful parts.

Classification
	Morphemes may be classified, on the basis of word formation, characteristics into the following types:
	Morpheme type Structure Bound Free root simple, made up of a single morpheme; a basis for compounding and affixation yes/no yes/no stem may be complex, made up of one or more morphemes; a basis for affixation yes/no yes/no affix prefix infix suffix suprafix simulfix circumfix simple yes no clitic proclitic enclitic simple yes (phonologically) yes (syntactically)
	Note: A clitic is a kind of morpheme that does not fit well in the above classification system because it is phonologically bound but syntactically free.