LATIN DICTIONARYLexicon Latīnum
suffix · masculinesecond declension

-ūcus

-ūcus m (genitive -ūcī, feminine -ūca)
Classical[uː.kʊs]Ecclesiastical[u.kus]

Meaning

  1. adjectivemorphemenounsuffixused to form attributive nouns from nominals, often names of plants.
    lact- (“milk”) + -ūcus → lactūca (“lettuce”), literally “[that with] milky [latex]”
  2. adjectivemorphemenounsuffixused to form deverbal nouns meaning “one who tends to do X”.
    mandō (“chew”) + -ūcus → mandūcus (“glutton”)
  3. adjectivemorphemenounsuffixused to form some adjectives.

Origins

Maybe extended from Proto-Italic *-kos, from Proto-Indo-European *-kos, *-ḱos, thought to originally be a 'relational' suffix (compare -icus). In that case, most likely earlier *-oicos < *-oy-ḱo-s.

Quick answers

What does -ūcus mean in Latin?
-ūcus, a suffix, means “used to form attributive nouns from nominals, often names of plants.; used to form deverbal nouns meaning “one who tends to do X”.; used to form some adjectives.”.
How do you pronounce -ūcus?
In classical Latin, [uː.kʊs]; in ecclesiastical (church) Latin, [u.kus].