Synonyms for Spacious (same or very similar meaning)
WordNet sense 1 (very large in expanse or scope):
broad, wide
WordNet sense 2 (above average in size or number or quantity or magnitude or extent):
big, large
WordNet sense 3 ((of buildings and rooms) having ample space):
roomy
WordNet sense 4 (large and roomy (`convenient' is archaic in this sense)):
commodious, convenient
From the ODE community, based on WordNet
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