COSIGNATORY Meaning of COSIGNATORY in English cosignator|y BrE AmE ˌkəʊ ˈsɪɡ nət‿ ə r |i AmE \ ˌkoʊ ˈsɪɡ nə tɔːr |i -toʊr i ▷ cosignator|ies iz Longman Pronunciation English Dictionary. Английский словарь произношений Longman. 2012