Definition of "sub" []

• Informal See submarine. (noun)
• Informal See submarine. See Regional Note at submarine. (noun)
• A substitute. (noun)
• To act as a substitute. (verb-intransitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The term sub-irrigated refers to the high water table that keeps the soil moist much of the year."
• "We all knew that not all political Gurus are well-versed in economics and the term sub-prime was quite foreign to them."
• "Sub-primes generally are for those individuals who have poor credit, hence the term sub-prime."