Synonyms for flat

noun

• a deflated pneumatic tire
• freight car without permanent sides or roof
• a suite of rooms usually on one floor of an apartment house
• a level tract of land
• a musical notation indicating one half step lower than the note named
• a shallow box in which seedlings are started
• scenery consisting of a wooden frame covered with painted canvas; part of a stage setting

adjective

• lacking the expected range or depth; not designed to give an illusion or depth
• not modified or restricted by reservations
• not reflecting light; not glossy
• lacking stimulating characteristics; uninteresting
• lacking taste or flavor or tang
• having a surface without slope, tilt in which no part is higher or lower than another
• sounded or spoken in a tone unvarying in pitch
• stretched out and lying at full length along the ground
• flattened laterally along the whole length (e.g., certain leafstalks or flatfishes)
• commercially inactive
• having a relatively broad surface in relation to depth or thickness
• having lost effervescence
• horizontally level
• lacking contrast or shading between tones
• (of a musical note) lowered in pitch by one chromatic semitone

adverb

• in a forthright manner; candidly or frankly