Flat (5)

'flat' is the definition.
(I know that flat can be written as level)
This is the entire clue.
(Other definitions for level that I've seen before include "Floor; surveying device" , "Even; a plane" , "Absolutely horizontal" , "Straight, even" , "Staying at same height" .)
'flat' is the definition.
(I know that flat can be written as plane)
This is the entire clue.
(Other definitions for plane that I've seen before include "Tool for smoothing wood" , "Tree - figure - aircraft" , "barked?" , "Flat surface; tree" , "that soars into the sky" .)
'flat' is the definition.
(I know that flat can be written as apartment)
This is the entire clue.
(Other definitions for apartment that I've seen before include "Flat (chiefly US)" , "Accommodation" , "place to live" , "Flat (mainly US)" , "19 across" .)
'flat' is the definition.
(level)
This is the entire clue.
(Other definitions for even that I've seen before include "Still - quits" , "draw" , "Flat - yet" , "Flat, regular" , "Going so far as to" .)
'flat' is the definition.
(similar in meaning)
This is all the clue.
(Other definitions for horizontal that I've seen before include "What this answer isn't!" , "Prone" , "even" , "Lying flat" .)