How many letters does the top answer for “the act or process of making slots, or mortises.” have?

The most common answer is slotting (8 letters).

Crossword clue: the act or process of making slots, or mortises.

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

slotting 8 letters web-def

a position in a grammatical linguistic construction in which a variety of alternative units are interchangeable

the act or process of making red. 50% similar → rubefaction

the act or process of making white. 50% similar → albification

the act or the process of making electrotypes. 50% similar → electrotyping