Infix Definition
An infix is a type of affix, a morpheme or a group of morphemes (the smallest linguistic units of meaning) that are inserted within a root word or stem to alter its meaning or create a new word. Unlike prefixes and suffixes, which are attached at the beginning or end of a root word respectively, infixes are inserted into the body of the word. While infixes are not common in English, they are widely used in many other languages, including Tagalog, Greek, and several Native American languages.
Although infixes aren’t as common as prefixes and suffixes in English, they do appear on occasion to help convey meaning in a grammatically correct manner.
One sentence summary: An infix is a word or word part (i.e., a morpheme) added to the middle of a word stem to alter the meaning, change a word's grammatical form, or as a type of wordplay.
As a reminder, a word stem is the part of the word that carries the lexical meaning. In essence, an infix splits up a word and adds meaning or emphasis to it with an additional morpheme.
Word: runner-up (meaning second place)
Stem: runner (the person or thing that takes second place)
Infix: runners-up (plural form)
Notice the -s is added to the root word, runner, instead of to the end of the entire hyphenated compound word (e.g., runner-ups); this is an example of an infix. Many people confuse this process with a process called tmesis, where an entire word is inserted into the body of a compound word.
Tmesis is the separation of a compound word by inserting another word for added emphasis in informal speech.
For example, for emphasis, you might say, "un-freaking-believable!" The original word is unbelievable, which is a compound (un+believable).
Fig. 1 - An infix is similar to those bonus pieces of bread in the middle of a towering sandwich.
Infix Morphemes
As mentioned, infixes are almost always composed with a word part or morpheme, so it may be helpful to define the term morpheme.
Morphemes are the smallest units of language that have meaning and can’t be further subdivided.
So a morpheme can be anything from a single letter—like the letter ‘s,’ which can indicate plurality—or an entire word, and anything in between, so long as it carries meaning.
An example of an infix in English is when you add the morpheme ‘s’ to the middle of the word father-in-law to make it plural. The correct form is fathers-in-law, not father-in-laws.
Infixation is a morphological complexity, which means it occurs on a morphological level.
Morphology is a division of linguistics that studies the smallest segments (morphemes) of language that carry meaning. To examine a word on a morphological level is to analyze its structure, including its individual parts like the stem and affixes.
Because an infix interrupts a word, it will usually sit between two morphemes of that word. It adds complexity to the word at hand, both in meaning and structure.
An infix shouldn’t be confused with an interfix, which shows up between two base words, while an infix appears inside a base word or word stem. For example, the word speedometer is connected by an 'o', which is an interfix. An infix always interrupts an existing word, which speedmeter is not.
Infixation Examples
While English does not typically use infixes in standard usage, they do occur in informal or colloquial language. An example is the use of "-bloody-" or "-freaking-" in words like "abso-bloody-lutely" or "un-freaking-believable".
In other languages, infixes are more common. For example, an Austronesian language spoken by the Tagalog people in the Philippines regularly uses infixation. The infix "-um" helps create the present and past tense of Tagalog verbs.
Word Stem | New Word (Present Tense) | New Word (Past Tense) |
Kain (eat) | Kumakain ako (I'm eating) | Kumain (I ate) |
Tawa (laugh) | Tumatawa siya (He's laughing) | Tumawa siya (He laughed) |
We can find another example of infixation in the language of Malay. See the infix er change the meaning of the words in the table below.
Word Stem | New Word |
Gigi (teeth) | Gerigi (toothed blade) |
Sabut (husk) | Serabut (disheveled) |
When to Use Infixes in the English Language
As previously stated, there aren't as many examples of infixes in the English language. You can't just insert any morpheme in the middle of any word and have it make sense. There are just a few specific instances that use infixation.
Infixes to Pluralize Hyphenated Compounds
The use of infixation to create the term fathers-in-law extends to other hyphenated compound words. Essentially, to make a compound word plural, you can't just add an a 's' to the end of the word, as you can with so many other types of words. Instead, you must add the 's' to the word stem, which is the part of the word that carries the lexical meaning. Sometimes the word stem is at the beginning of the compound, which would require the 's' to appear in the middle.
Compound Noun | Plural Compound Noun |
Passer-by | Passers-by |
Attorney-in-fact | Attorneys-in-fact |
Editor-in-chief | Editors-in-chief |
Brother-in-law | Brothers-in-law |
Colloquialism Infixation
You'll probably only hear these colloquialisms in very specific contexts, but both use the process of infixation, and most native English speakers inherently understand how to use them.
Remember, a colloquialism is an informal word or phrase typically used in a familiar conversation or setting.
The first is the infix "-iz" found in hip-hop slang.
House = hiz-ouse
Tour = tiz-our
Party = piz-arty
This style of slang is rather outdated, but you might still hear it used in an ironic sense. The infix "-iz" is inserted after the word-initial consonant—which is the first consonant of the word— to create a more "hip" version of the word.
The second colloquialism is called the Homeric infix, named after Homer Simpson from the TV show The Simpsons. Part of Homer's character is his lack of intelligence, so you might hear him insert the ma sound in the middle of a complex word. This psuedo-sophistimacation makes a mockery of an intellectual person or subject.
Fig. 2 - Is Homer Simpson's use of infix make him a linguistic genius?
For example, in season 9, episode 3 of The Simpsons, Homer picks up his daughter's saxophone and fondly calls it a "saxamaphone."
Although the morpheme "-ma has no inherent meaning, the context of the speaker (an unintelligent yet loveable moron named Homer) and the subject help to illustrate the intent, which is to illustrate the stupidity of the speaker. Others found this a funny way to poke fun at intellectuals, and so the tradition of the Homeric infix has lived on.
Expletive Infixes
There is debate among linguistics and rhetoricians as to whether the following is an example of tmesis or infixation:
Most infixes are morphemes, but in the case of expletive infixes, an entire word interrupts the continuous word absolutely. This phenomenon is exclusively seen with rude or expletive words.
Edu-freakin-cated
Halle-bloody-lujah
A-whole-nother
Few people explicitly know the rules as to where to place the expletive, and yet they seem to understand where it goes inherently. In English, the inserted element (whether it's an infix or an entire word) is placed right before a stressed syllable, usually the one with the strongest stress.
Infix Words vs. Tmesis
As previously mentioned, tmesis also involves inserting sounds into the middle of a word, but there are some significant differences between tmesis and infix words.
The noticeable difference between tmesis and infixation is that tmesis is the interruption of a compound word, whereas infixation is the interruption of a simple or non-compound word. Additionally, tmesis typically involves the insertions of whole words rather than affixes. It is the line between tmesis and expletive infixes that is often blurred.
While infixes may share phonological properties with tmesis, such as how they segment the word they're interrupting, they remain separate despite the similar definitions and uses.
Infix - Key takeaways
- An infix is a word or word part, called a morpheme, added to the middle of a word stem to alter the meaning.
- An infix is an affix, just like prefixes and suffixes.
- There are only four common instances of infixation in the English language: to pluralize hyphenated compound words, expletive infixes, and in the informal colloquialisms that add "-ma" and "-iz" (respectively) to the middle of words.
- The noticeable difference between tmesis and infixation is that tmesis is the interruption of a compound word, whereas infixation is the interruption of a simple or non-compound word.
- In English, the inserted element (whether it's an infix or an entire word) is placed right before a stressed syllable, usually the one with the strongest stress.
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