What's the plural form of line engraving? Here's the word you're looking for.
Answer
The noun line engraving can be countable or uncountable.
In more general, commonly used, contexts, the plural form will also be line engraving.
However, in more specific contexts, the plural form can also be line engravings e.g. in reference to various types of line engravings
or a collection of line engravings.