How many letters does the top answer for “a verse line having six metrical feet” have?

The most common answer is hexameter (9 letters).

Crossword clue: a verse line having six metrical feet

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

hexameter 9 letters wn-def

a verse line having six metrical feet

a verse line having eight metrical feet 71% similar → octameter

a verse line having five metrical feet 71% similar → pentameter

a verse line having four metrical feet 71% similar → tetrameter