Pronunciation: (ik-sten'siv),[key] —adj. 1. of great extent; wide; broad: an extensive area. 2. covering or extending over a great area: extensive travels. 3. far-reaching; comprehensive; thorough: extensive knowledge. 4. lengthy: an extensive journey. 5. great in amount, number, or degree: an extensive fortune; extensive political influence. 6. of or having extension: Space is extensive, time durational. 7. noting or pertaining to a system of agriculture involving the use or cultivation of large areas of land with a minimum of labor and expense (opposed to intensive).