Crossword Puzzle Sometimes warring groups

Clue: Sometimes warring groups

Warring groups (ARMIES with 6 letters)
School groups: Abbr. (PTAS with 4 letters)
Groups of numbers (MEDLEYS with 7 letters)
Poets' three-line groups (TERCETS with 7 letters)
Voting groups (BLOCS with 5 letters)
Entitled groups (ELITES with 6 letters)
TV groups (PANELS with 6 letters)
Course groups (FOURSOMES with 9 letters)
"Hmmmmm ..." [as hinted at by the three groups of black squares in the middle of the grid] (SOMETHINGSFISHY with 15 letters)
Belligerent sea groups (ARMADAS with 7 letters)