an upholstered seat with back and arms for two or more people 
WordReference Random House Learner's Dictionary of American English © 2025
so•fa /ˈsoʊfə/USA pronunciation  
n. [countable], pl. -fas. 
WordReference Random House Unabridged Dictionary of American English © 2025- Furniturea long upholstered couch with a back and two arms or raised ends.
 
so•fa 
(sō′fə),USA pronunciation n. 
- Furniturea long, upholstered couch with a back and two arms or raised ends.
 
- Arabic ṣuffah platform used as a seat
 - Turkish
 - 1615–25
 
Collins Concise English Dictionary © HarperCollins Publishers::
'sofa' also found in these entries (note: many are not synonyms or translations):
Lawson
 - Ottoman
 - arm
 - armpad
 - armrest
 - back order
 - backed
 - blend
 - bolster
 - borne
 - boudeuse
 - camelback
 - canapé
 - cast
 - channel back
 - chesterbed
 - chesterfield
 - club sofa
 - coffee table
 - confidente
 - convertible
 - couch
 - crest rail
 - cushion
 - davenport
 - davenport table.
 - daybed
 - divan
 - durrie
 - end table
 - fire
 - fluff
 - have
 - hideaway bed
 - hoist
 - independent
 - jockey
 - lay
 - lit de justice
 - loll
 - loose cover
 - lose
 - lounge
 - love seat
 - lyre-form sofa
 - modular
 - méridienne
 - ornate
 - overstuffed
 - plump