-tiu

• -siu

From Latin -īvus via rebracketing. The Latin suffix was typically added to the perfect passive participial stem of verbs, which for most verbs consists of the thematic vowel followed by t.

• IPA^(key): (Central, Balearic, Valencia) [ˈtiw]

-tiu (feminine -iva, masculine plural -ius, feminine plural -ives)

1. forms adjectives from verbs; the vowel of the infinitive is kept, i.e. -atiu, -etiu, -itiu.

Often takes the variant form -siu with verbs historically belonging to the Latin third conjugation. The form taken by this suffix can generally be predicted by the form taken by the suffix -ció, which often appears as -sió with these verbs. For instance, abrasió : abrasiu; obsessió : obsessiu; decisió : decisiu, etc.

• -iu

From Proto-Celtic *-tiyū; compare Latin -tiō.

• -thiu, -tu

-tiu f

1. forms verbal nouns

• Thurneysen, Rudolf (1940) [1909], D. A. Binchy and Osborn Bergin, transl., A Grammar of Old Irish, Dublin Institute for Advanced Studies, translation of Handbuch des Alt-Irischen (in German), →ISBN, § 730, page 451; reprinted 2017

-tiu m

1. alternative form of -tu (“-ness, -ity”)