intensive

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Of, relating to, or characterized by intensity.
• adjective Grammar Tending to emphasize or intensify.
• adjective Possessing or requiring to a high degree. Often used in combination.
• adjective Relating to or being a method especially of land cultivation intended to increase the productivity of a fixed area by means of an increase in capital and labor.
• adjective Physics Having the same value for any subdivision of a thermodynamic system.
• noun A linguistic element, such as the adverb extremely or awfully, that provides force or emphasis.

from The Century Dictionary.

• In agriculture, concentrated (cultivation): designating high culture, or the principle of a small area well tilled, the purpose being to secure the most from every acre of land by means of the application of labor and fertilizers and the most thorough tillage. Compare extensive, 5.
• In pathology, noting the treatment of disease by very large or frequently repeated doses, or by remedies of greatly increased strength or activity.
• Pertaining or referable to intensity or degree; increasing in intensity or degree; making or becoming intense; intensifying.
• Intense.
• Intent; unremitted; assiduous.
• In grammar, expressing intensity or a high degree of action or quality; serving to give force or emphasis: as, an intensive particle or prefix.
• Logical comprehension or depth; the sum of the characters predicable of a term; the sum of consequences from a given fact.
• noun Something serving to express intensity, or to give force or emphasis; specifically, in grammar, an intensive particle, word, or phrase.

from the GNU version of the Collaborative International Dictionary of English.

• noun That which intensifies or emphasizes; an intensive verb or word.
• adjective Stretched; admitting of intension, or increase of degree; that can be intensified.
• adjective obsolete Characterized by persistence; intent; unremitted; assiduous; intense.
• adjective (Gram.) Serving to give force or emphasis.
• adjective (Agric.) Designating, or pertaining to, any system of farming or horticulture, usually practiced on small pieces of land, in which the soil is thoroughly worked and fertilized so as to get as much return as possible; -- opposed to extensive.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective Thorough, to a great degree, with intensity.
• adjective Demanding, requiring a great amount.
• adjective Highly concentrated.
• noun linguistics Form of a word with a stronger or more forceful sense than the root on which the intensive is built.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a modifier that has little meaning except to intensify the meaning it modifies
• adjective tending to give force or emphasis
• adjective of agriculture; intended to increase productivity of a fixed area by expending more capital and labor
• adjective characterized by a high degree or intensity; often used as a combining form