From Longman Dictionary of Contemporary Englishextensiveex‧ten‧sive /ɪkˈstensɪv/ ●●○W3 adjective 🔊 🔊 1SIZElarge in size, amount, or degree 🔊 The house stands in extensive grounds. 🔊 Fire has caused extensive damage to the island’s forests. 🔊 the extensive use of pesticides2LOT/LARGE NUMBER OR AMOUNTcontaining or dealing with a lot of information and details 🔊 Extensive research is being done into the connection between the disease and poor living conditions. 🔊 The exhibition has received extensive coverage in the national press. —extensively adverb 🔊 As a student, he travelled extensively in the Middle East.