---

All answers having "Quash" as clue:

3 Character Answers:

---

END

NIX



4 Character Answers:

---

HALT

KILL

STOP

VETO



5 Character Answers:

---

ABATE

ANNUL

SITON



6 Character Answers:

---

STEPON

SUBDUE



7 Character Answers:

---

RESCIND

SQUELCH



8 Character Answers:

---

SUPPRESS