—adj.
1 thorough, vigorous; directed to a single point, area, or subject (intensive study; intensive bombardment).
2 of or relating to intensity as opp. to extent; producing intensity.
3 serving to increase production in relation to costs (intensive farming methods).
4 (usu. in comb.) Econ. making much use of (a labour-intensive industry).
5 Gram. (of an adjective, adverb, etc.) expressing intensity; giving force, as really in my feet are really cold.
—n. Gram. an intensive adjective, adverb, etc.
Phrases and idioms:
intensive care medical treatment with constant monitoring etc. of a dangerously ill patient (also (with hyphen) attrib.: intensive-care unit).
Derivatives:
intensively adv. intensiveness n.
Etymology: F intensif -ive or med.L intensivus (as INTEND)
Useful english dictionary. 2012.