This is the 376th most frequent Icelandic word.
deildinni
"Deildinni" means "the department" or "the division" in English.
Here, "deildinni" is the dative singular of "deild" (department) and refers to a location, indicating where the meeting will take place.
Við munum hitta í deildinni á morgun.
We will meet in the department tomorrow.
In this sentence, "deildinni" again is the dative singular of "deild" and signifies the place where the discussion occurred.
Hún tók þátt í umræðu í deildinni.
She participated in a discussion in the department.
Here, "deildinni" is used to denote the context or environment (department) where the support existed.