colleague (female)
The article is part of the word: die Kollegin. That way you learn the gender with it.
On the card “colleague (female)”, ripiti also accepts die Mitarbeiterin. Not the other way round: for die Mitarbeiterin, die Kollegin is not accepted.
Remember die Kollegin for good. ripiti brings the word back just before you forget it, with these sentences. Free, no account needed, works offline.
practise die Kollegin in ripiti