How many letters does the top answer for “the lap or bosom. chaucer.” have?

The most common answer is barm (4 letters).

Crossword clue: the lap or bosom. chaucer.

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

barm 4 letters web-def

a commercial leavening agent containing yeast cells; used to raise the dough in making bread and for fermenting beer or

of or pertaining to the lap or bosom. 50% similar → gremial