Infix

An infix is an affix inserted inside a word stem (an existing word). It contrasts with adfix, a rare term for an affix attached to the outside of a stem, such as a prefix or suffix.

When marking text for interlinear glossing, most affixes are separated with a hyphen, but infixes are separated with ⟨angle brackets⟩.

English has almost no true infixes (as opposed to tmesis), and those it does have are marginal. A few are heard in colloquial speech, and a few more are found in technical terminology.

None of the following are recognized in standard English.

The use of 'expletive infixes' such as fucking and bloody, which are words rather than affixes, is known as tmesis.

The present tense of some Proto-Indo-European verbs adds a nasal infix (m, n) to the basic root; the stems of the other tenses have the root without the infix.

In Nicaragua and neighboring countries, the Spanish diminutive affix becomes an infix ⟨it⟩ in names: Óscar [ˈoskar] → Osquítar [osˈkitar] (cf. standard Oscarito); Edgar → Edguítar; Victor → Victítor.

Arabic uses a common infix, ⟨t⟩ ت for Form VIII verbs, usually a reflexive of Form I. It is placed after the first consonant of the root; an epenthetic i- prefix is also added since words cannot begin with a consonant cluster. An example is اجتهد ijtahada "he worked hard", from جهد jahada "he strove". (The words "ijtihad" and "jihad" are nouns derived from these two verbs.)

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