From Proto-Italic *-ātos, from Proto-Indo-European *-eh₂tos. A "pseudo-participle" possibly related to -tus, though similar formations in other Indo-European languages show that it was distinct from it already in Indo-European times.
Cognate to Proto-Slavic *-atъ, Proto-Germanic *-ōdaz (English -ed (“having”)).
-ātus m (feminine -āta, neuter -ātum); first/second declension
- -ed, -ate, -like. Used to form adjectives from nouns indicating the possession of a thing or a quality.
- barba (“beard”) → barbātus (“bearded, having a beard”)
- rēticulum (“small net”) → rēticulātus (“reticulated, net-like”)
- albus (“white”) → albātus (“clothed in white”)
By rebracketing of action nouns in -tus, -tūs formed from first conjugation verbs, such as mercātus (mercor + -tus) or pecūlātus (peculor + -tus), where -ā- is actually part of the stem.
- Form of -tus appended to nouns
- triumvir + -ātus → triumvirātus
- episcopus + -ātus → episcopātus
- apostolus + -ātus → apostolātus