Probably allas + -ikko, which derives a number of nature nouns such as matalikko (“wash, shallow water”) and lammikko (“puddle”).
allikko
| Inflection of allikko (Kotus type 4*A/laatikko, kk-k gradation) | |||
|---|---|---|---|
| nominative | allikko | allikot | |
| genitive | allikon | allikkojen allikoiden allikoitten | |
| partitive | allikkoa | allikkoja allikoita | |
| illative | allikkoon | allikkoihin allikoihin | |
| singular | plural | ||
| nominative | allikko | allikot | |
| accusative | nom. | allikko | allikot |
| gen. | allikon | ||
| genitive | allikon | allikkojen allikoiden allikoitten | |
| partitive | allikkoa | allikkoja allikoita | |
| inessive | allikossa | allikoissa | |
| elative | allikosta | allikoista | |
| illative | allikkoon | allikkoihin allikoihin | |
| adessive | allikolla | allikoilla | |
| ablative | allikolta | allikoilta | |
| allative | allikolle | allikoille | |
| essive | allikkona | allikkoina | |
| translative | allikoksi | allikoiksi | |
| abessive | allikotta | allikoitta | |
| instructive | — | allikoin | |
| comitative | See the possessive forms below. | ||