LATIN DICTIONARYLexicon Latīnum
suffixfirst/second-declension suffix

-icus1

-icus (feminine -ica, neuter -icum)
Classical[ɪ.kʊs]Ecclesiastical[i.kus]

Meaning

  1. morphemesuffixof or pertaining to; belonging to; derived from; connected with: -ic, -ish
    cīvis (“citizen”) + -icus → cīvicus (“civic; pertaining to citizens”)
    Gallus (“a Gaul; Gallic”) + -icus → gallicus (“of or pertaining to Gaul or the Gauls; Gallic, Gaulish”)
  2. morphemesuffixused to form some substantivized nouns from other nouns
    manus f (“hand”) + -ica → manica (“sleeve”)

Origins

Inherited from Proto-Italic *-ikos. Cognate with Ancient Greek -ικός (-ikós), Proto-Germanic *-igaz (Old High German and Old English -ig, Gothic -𐌴𐌹𐌲𐍃 (-eigs)), Sanskrit -इक (-ika), Proto-Slavic *-ьcь.

Descendants
  • Catalan-ic
  • English-ic
  • English-ick
  • French-ique
  • Italian-ico
  • Portuguese-ico
  • Portuguese-igo
  • Portuguese-ego
  • Romanian-ec
  • Romanian-ic
suffix · masculinesecond declension
-īcus2
-īcus m (genitive -īcī, feminine -īca)
Classical[iː.kʊs]Ecclesiastical[i.kus]

Meaning

  1. adjectivemorphemenounsuffixused to form nouns from verbs or nouns
    lectus (“bed”) + -īca → lectīca (“litter”)
  2. adjectivemorphemenounsuffixused to form adjectives from verbs or nouns
    pudet (“to cause shame”) + -īcus → pudīcus (“chaste, pure”)

Origins

Probably ultimately extended from Proto-Indo-European *-kos, *-ḱos (Etymology 1), the -ī- may come from an instrumental case form. Compare -ūcus and also, -ītus. Compare also other words containing a velar suffix such as fēlīx.

Quick answers

What does -icus mean in Latin?
-icus, a suffix, means “of or pertaining to; belonging to; derived from”.
How do you pronounce -icus?
In classical Latin, [ɪ.kʊs]; in ecclesiastical (church) Latin, [i.kus].