How many letters does the top answer for “a room enclosed largely with glass and affording exposure to the sun” have?

The most common answer is solarium (8 letters).

Crossword clue: a room enclosed largely with glass and affording exposure to the sun

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

solarium 8 letters wn-def

a room enclosed largely with glass and affording exposure to the sun

sunporch 8 letters wn-def

a room enclosed largely with glass and affording exposure to the sun

sunroom 7 letters wn-def

a room enclosed largely with glass and affording exposure to the sun