Was CSS Virginia the first coastal-defence ship?

Could CSS Virginia be considered the first coastal-defence ship?

Not as cleanly as USS Monitor, because Virginia was converted from a sea-going frigate hull rather than designed for the coastal role from the start.

The answer turns on design origin rather than merely where a ship fought. CSS Virginia was reconstructed on the hull of the former steam frigate USS Merrimack, a vessel conceived for sea-going service. That lineage makes her harder to describe as a purpose-built coastal defender. USS Monitor provides the cleaner example because limited-water combat, armor, and turret firepower shaped her from the outset.