What is the meaning of -tus?

alternative form of -us (forms nouns from verbs, describing an action or event)

romanization of -𐍄𐌿𐍃

Forms the past participle of verbs.

Forms adjectives having the sense "provided with".

‎errō (errā-) (“wander”) + ‎-tus → ‎errātus

‎audiō (audī-) (“hear”) + ‎-tus → ‎audītus

‎moneō (monē-) (“advise, remind”) + ‎-tus → ‎monitus

‎augeō (augē-) (“increase”) + ‎-tus → ‎auctus

Forms action nouns from verbs.

Forms collective/abstract nouns from adjectives or other nouns.

-ly; used to form adverbs.

Source: wiktionary.org