What is the meaning of -iera?

forms nouns from nouns, denoting a container or cover; container

forms nouns from nouns, denoting an area where something grows or is found; field, patch, mine, quarry

added to nouns to form other concrete nouns; -er; -or

female equivalent of -iere

first/third-person singular imperfect subjunctive of -er

Source: wiktionary.org