How many letters does the top answer for “to join or fit together; to unite. halliwell.” have?

The most common answer is pan (3 letters).

Crossword clue: to join or fit together; to unite. halliwell.

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

pan 3 letters web-def

cooking utensil consisting of a wide metal vessel