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Dictionary: Requiring or having a large expenditure of labor in comparison to capital: “Intrigue and subversion are labor-intensive undertakings” (George F. Kennan).

Investment Dictionary:A process or industry that requires large amounts of human effort to produce goods

Financial & Investment Dictionary: Requiring large pools of workers. Said of an industry in which labor costs are more important than capital costs. Deep-shaft coal mining, for instance, is labor-intensive.

Accounting Dictionary: Industry or company where labor costs are more important than capital costs. Labor intensive companies generally have greater earnings stability than Capital Intensive ones, because the former have a higher percentage of variable costs, while the latter have a higher percentage of fixed costs. However, labor intensive firms may experience difficulty during inflation due to employee discontent resulting from the decline in real earnings. But higher wage rates would be passed on in higher prices.

Economics Dictionary: A term describing industries that require a great deal of labor relative to capital (compare capital-intensive). Examples of labor-intensive industries are forms of agriculture that cannot make use of machinery and service industries, such as restaurants.

Wikipedia: Labor intensity is the relative proportion of labor (compared to capital) used in a process. The term "labor intensive" can be used when proposing the amount of work that is assigned to each worker/employee (labor), emphasizing on the skill involved in the respective line of work.

Investment Dictionary. Copyright ©2000, Investopedia.com - Owned and Operated by Investopedia Inc. All rights reserved. 

Financial & Investment Dictionary. Dictionary of Finance and Investment Terms. Copyright © 2006 by Barron's Educational Series, Inc. All rights reserved. 

Accounting Dictionary. Dictionary of Accounting Terms. Copyright © 2005 by Barron's Educational Series, Inc. All rights reserved. 

Economics Dictionary. The New Dictionary of Cultural Literacy, Third Edition Edited by E.D. Hirsch, Jr., Joseph F. Kett, and James Trefil. Copyright © 2002 by Houghton Mifflin Company. Published by Houghton Mifflin. All rights reserved. 

Wikipedia. This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Labor intensity".

http://www.investopedia.com/terms/l/laborintensive.asp

What Does Labor Intensive Mean?
A process or industry that requires a large amount of labor to produce its goods or services. The degree of labor intensity is typically measured in proportion to the amount of capital required to produce the goods/services; the higher the proportion of labor costs required, the more labor intensive the business. 
Labor intensive industries include restaurants, hotels, agriculture and mining

Investopedia explains Labor Intensive
Advances in technology and worker productivity have moved some industries away from labor-intensive status, but many still remain. 

Labor costs are considered variable, while capital costs are considered fixed. This gives labor-intensive industries an advantage in controlling expenses during market downturns by controlling the size of the employee base. Disadvantages include limited economies of scale (you can't pay workers less by hiring more of them!) and susceptibility to wage forces within the labor market. 

http://www.economywatch.com/world-industries/labor-intensive.html

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Labor Intensive Industry refers to that industry, which requires substantial amount of human labor to produce the industrial products. As the name suggests, these labor intensive industries use labor intensively. This means, the proportion in which labor is used for production is much higher than the proportion of capital.

In these labor intensive industries, labor costs are much more important than the capital costs. Labor intensive industries usually do not carry high fixed cost. On the contrary, higher percentage of variable costs is incurred in the labor intensive industries. As these industries do not involve high level of fixed cost or high level of maintenance cost, they hold high earning potential. But, in case of high level of inflation in the Economy, the labor intensive industry can suffer to some extent. This is because, in the times of high level of inflation, the laborers can reveal their unwillingness to work at the same level of wage, as inflation lowers their real earnings.

Hospitality industry and coal mining industry are the industries, which hold a labor intensive industry structure. For the under developed and developing economies, labor intensive industry structure can be proved to be a better option than a capital intensive one. The countries, which are not rich and generate low level of income, labor intensive industry can bring economic growth and prosperity. In most of the cases, these low income countries suffer from scarcity of capital but are blessed with abundant labor force. If they can use this abundant labor force properly in their industry production, then they can experience industrial growth. Supply of perfectly skilled labor to any industry can trigger the industry growth rate. In this way, the under developed countries can improve their industrial economy without doing heavy capital investment.

Moreover, exportation of the products manufactured by labor intensive industries can strengthen the export base of any developing Country. These exports help the economies in earning foreign exchange, which can be used for importing essential goods and services. As the labor intensive industries generate employment on a large scale, they in a way contribute to economic well being.

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