How many letters does the top answer for “composer of cello concerto” have?

The most common answer is dvorak (6 letters).

Crossword clue: composer of cello concerto

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

dvorak 6 letters wd-fact-v3

Czech composer who combined folk elements with traditional forms (1841-1904)

elgar 5 letters wd-fact-v3

British composer of choral and orchestral works including two symphonies as well as songs and chamber music and music fo

composer of brandenburg concertos 50% similar → bach

composer of cello suites 50% similar → bach

composer of clarinet concerto 50% similar → nielsen

composer of concerto for orchestra 50% similar → bartok

composer of harpsichord concertos 50% similar → bach

composer of italian concerto 50% similar → bach

composer of piano concerto 50% similar → ravel

composer of violin concerto 50% similar → berg, sibelius