This time of the year, I say Hyviä lomillepääsiäisiä!
This, because it is Eastertime and other people say Hyvää pääsiäistä! ((Have a) happy Easter!) or Hyvää pääsiäislomaa! ((Have a) happy Easter holiday!).
That thing which I say, I say because I have an irrational dislike of going with the flow, and a rational dislike of religion. I try to avoid implicit religious wishes; and Easter has more religious connotations than, for example, a carefully neutered and secularized community-and-family holiday like Christmas. (“No, we’re not secularizing Christmas… pay no attention to the reward-in-heaven god-child being replaced by a rotund red symbol of earthly rewards for good deeds… I’m sure your need to remind us of remembering the true meaning of Christmas every time when starting to speak of the child doesn’t in any way indicate a shift in the meaning away from yours…”)
Hyvää is the same in both wishes — hyvä would be good, nice, enjoyable, and hyvää is the same conjugated to fit “(have a) nice (something)”. (Well er uh I think hyvää is an adjective in the same partitive case as that noun which follows it would be in but I don’t know; I just speak the Finnish language, I don’t understand it. Finnish grammar is madness.)
Pääsiäinen is Easter, but if you look at the word, it sounds and looks like it could have something to do with verbs like päästä, to be allowed or let go, or päästää, to allow or let go. Päästän koirat irti! — I’ll release the hounds!, or Erkki pääsi vankilasta, Erkki, a hypothetical character, got out of prison. Pääsiäinen is not something that immediately looks like a word of smaller parts in Finnish as currently spoken, but once you look it looks like an oldy-timey way of meaning “the-thing-or-event-related-to-releases”. This is probably the original meaning of the word — but this is not what anybody think about when the word is used in a standard construction.
Thus, pääsiäisloma would be “the Easter holiday/vacation”, but if you turn the words around into lomillepääsiäinen, it becomes something new, something where it is not obvious whether the p-part refers to the holiday or the word seemingly embedded in it, and the word seems best understood like this:
loma : holiday
lomille : to-the-holidays
pääsiäinen : the-event-of-being-released,
lomillepääsiäinen : the-event-of-being-released-to-go-on-the-holidays, the event of the time or occasion when or where you are allowed to burst the bonds of this surly work and go have some free time.
Which I think is something nice to express at people: You gets to go and have a holiday! Happy occasion! See you in a week! Hooray!
Then again, at times I hear Hyvää viikonloppua!, (have a) good weekend, and I am compelled to answer Kohtuuhyvää viikonloppua!, (have a) reasonably okay / moderately good weekend!
Or Ihan tavallista viikonloppua! — (have a) perfectly ordinary weekend.
I could even say Siedettävää viikonloppua — (have a) bearable weekend. (Sietämätöntä would be, in this phrase, unbearable.) Except with my dialect it would come out as sii’ettävvöö.
Or — you’re seeing how my mind works, right? — I think I should say Nähdään maanantaina!, see you on Monday — and I say instead Nähdään maanantaina, ellei sokeuduta sitä ennen! — which would be, see you on Monday, unless before that we lose our sight.
Also, päästäinen means “a shrew”, but that’s not related to anything. Also a shrew can be, Wikipedia tells me, popularly called a nokkahiiri, or a beak mouse.
Now you know this, too.
Finally, there are six species of shrew that live in Finland: the forest shrew, the black shrew, the eastern shrew, the infirm shrew, the dwarf shrew, and the water shrew. You could assemble a cartoon cast of them, except it would be horribly racist.