- Diminutive suffix for feminine nouns.
- Suffix for feminine nouns which means "type of".
Originally a variant of -ella used on verbs ending in -ata, -ota, -ätä, having developed by vowel contraction: -Aðele- (-oðele-) > -A.ele- (-o.ele-) > -Aile- (-oile-). Denominal use has been innovated in literary Finnish in the 20th century.
-illa (front vowel harmony variant -illä)
- Forms frequentative verbs. The resulting verb often describes a more or less leisurely or long-lasting activity, or an activity that is not overly goal-oriented.
- Forms action verbs which denote an activity closely related with a noun.
- Hakulinen, Lauri. 1941–2000. Suomen kielen rakenne ja kehitys ('The Structure and Development of the Finnish Language'). Helsinki: Otava/Helsingin yliopisto.
-illa (masculine counterpart -illo)
- If the noun has a final vowel (usually -a), it is dropped before adding -illa.
- In most cases, -illa is used simply to indicate a small or endeared thing, without changing the basic meaning of the noun; however, in some cases, it is used to effect a greater change in meaning, such as bombilla (“light-bulb”), from bomba (“bomb”).
- Different nouns tend to prefer different diminutive suffixes (see synonyms below), though some nouns accept multiple diminutives and there is often regional or personal variation.
- For masculine nouns ending in “-a”, there is some alternation between the gender-reflecting diminutive -illo and the ending-reflecting diminutive -illa. When the latter is used, -ill- may be considered an infix.