After solving the clues, we realize that the groups point to alphabetized lists of words which not only rhyme, but have their endings spelled the same. The flavortext and enumeration indicate that there is a word missing from each group.
| Words | Missing |
|---|---|
| CHUTE, CUTE, (5), JUTE, LUTE, MUTE | FLUTE |
| BAGGER, (6), JAGGER, NAGGER, STAGGER, SWAGGER | DAGGER |
| AGREEING, (5), FLEEING, FREEING, KNEEING, SEEING | BEING |
| (9), ASTOUNDING, COMPOUNDING, CONFOUNDING, RESOUNDING, SURROUNDING | ABOUNDING |
| BLOUSE, GROUSE, HOUSE, LOUSE, MOUSE, (6) | SPOUSE |
Each of those words is synonymous with a member of a final group of words, which also has a single missing word.
The missing word is the puzzle’s answer, STRIFE.