di ‧ ag ‧ o ‧ nal /daɪˈæɡən ə l/ BrE AmE adjective
[ Date: 1500-1600 ; Language: Latin ; Origin: diagonalis , from Greek diagonios 'from angle to angle' , from gonia 'angle' ]
1 . a diagonal line is straight and joins two opposite corners of a flat shape, usually a square ⇨ horizontal , vertical
2 . following a sloping angle:
diagonal parking spaces
—diagonal noun [countable]
—diagonally adverb :
The path goes diagonally across the field.