As a verb vanquish
is to defeat, to overcome.
As an adjective vanquishable is
that can be vanquished; defeatable, conquerable.
Other Comparisons: What's the difference?
To defeat, to overcome.
- They vanquished the rebels in all encounters.
- This bold assertion has been fully vanquished in a late reply to the Bishop of Meaux's treatise.
That can be vanquished; defeatable, conquerable.