Definition from Wiktionary, the free dictionary
- An older form of syksy.
- This form can be used only in nominative, in other cases it is replaced with the cases of syksy.
- Syys is still very frequent as a former part of a compound where it signifies "autumnal". For instance, syysmarkkinat means "an autumnal fair", i.e. a fair that takes place in autumn.