The most common use of the term „minelayer“ is a naval ship used for deploying sea mines. A naval minelayer can vary considerably in size, from coastal boats of several hundred tonnes in displacement to destroyer ships of several thousand tonnes displacement. In my game minelayer is a destroyer.
Destroyer is a fast, maneuverable, long-endurance warship intended to escort larger vessels in a fleet, convoy or battle group and defend them against smaller powerful short-range attackers.
In my game they look like this: