pro ‧ lon ‧ ga ‧ tion /ˌprəʊlɒŋˈɡeɪʃ ə n $ ˌproʊlɒːŋ-/ BrE AmE noun
1 . [singular, uncountable] the act of making something last longer
prolongation of
the prolongation of life
2 . [countable] something added to another thing which makes it longer
pro ‧ lon ‧ ga ‧ tion /ˌprəʊlɒŋˈɡeɪʃ ə n $ ˌproʊlɒːŋ-/ BrE AmE noun
1 . [singular, uncountable] the act of making something last longer
prolongation of
the prolongation of life
2 . [countable] something added to another thing which makes it longer
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012