This is the 545th most frequent Finnish word.
toiselle
"Toiselle" means "to the other" in English.
Here, "toiselle" signifies the recipient of help (to another person).
Autoin toiselle ihmiselle löytämään kadonneen avaimen.
I helped another person to find the lost key.
In this sentence, "toiselle" refers to a specific person for whom the seat is reserved (for another).
Tämä paikka on varattu toiselle vieraalle.
This seat is reserved for another guest.
The word 'toiselle' functions as a dative-like form of 'toinen,' indicating the one receiving the action.