Definition of "Flat" :
noun: a suite of rooms usually on one floor of an apartment house
noun: scenery consisting of a wooden frame covered with painted canvas; part of a stage setting
noun: a deflated pneumatic tire
noun: a shallow box in which seedlings are started
noun: freight car without permanent sides or roof
noun: a musical notation indicating one half step lower than the note named
noun: a level tract of land
"The salt flats of Utah."
adjective: commercially inactive
"Flat sales for the month."
adjective: not reflecting light; not glossy
"Flat wall paint."
adjective: having a relatively broad surface in relation to depth or thickness
"Flat computer monitors."
adjective: lacking the expected range or depth; not designed to give an illusion or depth
"A flat two-dimensional painting."
adjective: having a surface without slope, tilt in which no part is higher or lower than another
"A flat desk."
adjective: lacking contrast or shading between tones
adjective: horizontally level
"A flat roof."
adjective: stretched out and lying at full length along the ground
"Found himself lying flat on the floor."
adjective: sounded or spoken in a tone unvarying in pitch
adjective: (of a musical note) lowered in pitch by one chromatic semitone
adjective: not modified or restricted by reservations
"A flat refusal."
adjective: having lost effervescence
adjective: lacking stimulating characteristics; uninteresting
"A flat joke."
adjective: lacking taste or flavor or tang
adjective: flattened laterally along the whole length (e.g., certain leafstalks or flatfishes)
adverb: in a forthright manner; candidly or frankly
"Came out flat for less work and more pay."
adverb: with flat sails
"Sail flat against the wind."