Probably from monni + -tti, inspired by the given name Martti, Mortti, etc.
mortti
| Inflection of mortti (Kotus type 5*C/risti, tt-t gradation) | |||
|---|---|---|---|
| nominative | mortti | mortit | |
| genitive | mortin | morttien | |
| partitive | morttia | mortteja | |
| illative | morttiin | mortteihin | |
| singular | plural | ||
| nominative | mortti | mortit | |
| accusative | nom. | mortti | mortit |
| gen. | mortin | ||
| genitive | mortin | morttien | |
| partitive | morttia | mortteja | |
| inessive | mortissa | morteissa | |
| elative | mortista | morteista | |
| illative | morttiin | mortteihin | |
| adessive | mortilla | morteilla | |
| ablative | mortilta | morteilta | |
| allative | mortille | morteille | |
| essive | morttina | mortteina | |
| translative | mortiksi | morteiksi | |
| abessive | mortitta | morteitta | |
| instructive | — | mortein | |
| comitative | See the possessive forms below. | ||