I know that rockarna is the phrase for "the coats". But I've been living with a Swedish family here for a year, and they always use the word "Jacka" for outdoor coats
de (third-person plural nominative, dative and accusative dem, genitive deras, reflexive sig)
(Sweden) IPA: /dɔm/, (formal) IPA: /deː/, (dialectal) IPA: /diː/, IPA: /dɪ/.
So apparently it's usually pronounced like dem... That explains why I kept mishearing it.
Sorry for my ignorance, but what is the difference between (in the moderated language) a coat and a jacket?
I think the coat is longer. Just search on google jacket and coat you will be able to understand the differnce between them