noun
icing
EYE-sing/ˈaɪsɪŋ/
A covering that forms like a layer of ice.
A baker spreads smooth icing over a plain cake with a spatula.

Etymology
The verb ice originally meant “cover with ice.” In confectionery, icing named a coating of hardened sugar, shifting from an icy covering to a sweet one.
In context
it is a beautiful cupcake with this beautiful blue icing on the top
More examples
- The lemon icing dries to a thin shell.
- Icing on the wings can make flying dangerous.
- Freezing rain causes heavy icing on power lines.
Forms
icing · icings
ice verb — To cover with ice or frosting.