How many letters does the top answer for “a light four-wheeled horse-drawn carriage; has two or four seats” have?

The most common answer is surrey (6 letters).

Crossword clue: a light four-wheeled horse-drawn carriage; has two or four seats

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

surrey 6 letters wn-def

a light four-wheeled horse-drawn carriage; has two or four seats