-ir

Etymology
, the ending of the present active infinitive form of fourth conjugation verbs, which merged with, , from which come the -eix- infix.

Usage notes

 * does not count as a third conjugation verb, belonging to the second conjugation.

Etymology
, the ending of the present active infinitive form of fourth conjugation verbs. Cognate with 🇨🇬, 🇨🇬, 🇨🇬 and, etc.

Usage notes

 * Most verbs with infinitives in -ir are marked by the once-inchoative infix in many parts of their conjugation, as well as in various derived words; two such verbs are  and . A fair number of these have English counterparts in ; some such examples are, , , and.
 * Many verbs with infinitives in -ir have an inchoative meaning. Examples include, , , , and.
 * A sizable group of verbs have infinitives in -ir but do not use the infix, and are otherwise fairly regular; these include, among others, the common verbs , , (but these examples are also irregular, with  instead of *sortis). An irregular -ir verb which is truly conjugated exactly as a regular -ir verb except only without the infix (although it is dated and has a regular alternative conjugation) is.
 * This suffix is spelled on a few verbs where the previous syllable ends in a vowel, such as  and . Additionally, it is spelled  on the verb, by analogy with the related but irregular verb , and the verb.
 * Not all verbs whose infinitives happen to end in these letters can truly be said to have this suffix; in particular, a fair number of irregular verbs have infinitives in the unrelated suffix.

Usage notes

 * affixed following the verb stem
 * This form follows in active voice verbs
 * following in middle voice verbs the affix becomes

Etymology
Modeled after and.

Etymology
From, the ending of the present active infinitive form of fourth conjugation verbs, which merged with , , from which come the -iss- and -isc- infix.

Etymology
From, the ending of the present active infinitive form of fourth conjugation verbs.

Etymology
From, from.

Suffix

 * 1)  a suffix used to create agent nouns from verbs

Usage notes

 * Agent nouns formed with this suffix are rare, and mostly found in old poetry.

Etymology
From, from , the ending of the present active infinitive form of fourth conjugation verbs. In some verbs, it is a reflex of of the third conjugation.

Etymology
From, the ending of the present active infinitive form of fourth conjugation verbs.

Conjugation
Below are the suffixes for the regular conjugation of -ir verbs

Usage notes
-ir causes i-affection of internal vowels, for example,.