As-salaamu `alaykum.
The `Arabic word, جمعة transliterated as jumu`ah does indeed mean and correspond to Friday. The word جماعة translierated as jamaa`ah means assembly, congregation, gathering, community, group etc (the word is also used to describe the congregational prayer). They are two seperate words which are (both) often loosely and poorly transliterated as jumah, which leads many to confusion (you're not the only one). The two words both stem from the same root, جمع which means, gathering, collection etc.
I hope this explains.
Wasalaamu `alaykum