kartongen is the masculine singular definite of kartong.

kartongN

Kven

kartonkiN

Norwegian Bokmål – Kvendict-nob-fkv/src/N_nobfkv.xml:949Edit on GitHub Suggest

kartoŋŋaN; kartoŋgaN

Norsk-nordsamisk ordbokdict-nob-sme/src/N_nobsme.xml:55097Edit on GitHub Suggest

Case	Sg	Pl
Indef	kartong	kartonger
Def	kartongen	kartongene