What is the meaning of -m?

Used to form (pro)nouns taking on the quality of the suffixed determiners, numbers, verbs and nouns.

Forms comparative adjectives.

Forms nouns from verbs.

my (first-person singular, single possession)

First-person singular personal suffix:

  1. Definite forms of transitive verbs (followed by a linking vowel in indicative present/past and subjunctive moods; with no linking vowel in conditional mood).

    Definite forms of transitive verbs (followed by a linking vowel in indicative present/past and subjunctive moods; with no linking vowel in conditional mood).

    Indefinite forms of -ik verbs.

    Forming conjugated infinitives (here: “for me to do something”).

    Declined and postpositional forms of the first-person personal pronoun én (I).

    Added to a verb (or rarely to a noun) to form a noun. No longer productive in this sense.

    No longer productive in this sense.

    Alternative form of -mo

    first-person singular suffix

    Forms verbal nouns of A III (hiatus) verbs

    Plural suffix (with m-declension nouns)

    and

    past-tense first-person singular suffix

    first-person singular suffix

    Evidential suffix, first-hand information. Indicates that the speaker has direct evidence/knowledge of some fact, having experienced it, seen it, heard it, etc.

    Used to mark an open-ended question; less formal than -taq.

    First-person singular possessive suffix denoting singular possession in words ending in a vowel.

    Form of -im after a vowel.

    Source: wiktionary.org