Meaning of SPACING in English

SPACING

spac ‧ ing /ˈspeɪsɪŋ/ BrE AmE noun [uncountable]

the amount of space between the printed letters, words, or lines on a page

single spacing (=lines with no empty lines between them)

double spacing (=lines with one empty line after each one)

Longman Dictionary of Contemporary English.      Longman - Словарь современного английского языка.