sikken

A contraction of se (“see”) hvilken (“what, which”).

sikken (neuter sikket, plural and definite singular attributive sikke)

(translates to) what (such)
(adverbial) what (such), how
Sikke en dag! or Sikken en dag!
What a day!

As an adjective only preceding a noun in an exclamation of surprise, admiration, displeasure or regret. The pronoun hvilken is used synonymously.

As an adverbial in the form sikke or sikken.

Danish