How many letters does the top answer for “the cavity in which the large intestine begins and into which the ileum opens” have?

The most common answer is caecum (6 letters).

Crossword clue: the cavity in which the large intestine begins and into which the ileum opens

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

caecum 6 letters wn-def

the cavity in which the large intestine begins and into which the ileum opens

cecum 5 letters wn-def

the cavity in which the large intestine begins and into which the ileum opens