Definition

• Technical debt is a neologistic metaphor referring to the eventual consequences of poor software architecture and software development within a codebase.
• Unaddressed technical debt increases SoftwareEntropy?.
• -- See for more: ​http://en.wikipedia.org/wiki/Technical_debt

Other opinions

MartinFowler suggested the following definition for technical debt:

Technical debt, is similar to a financial debt. Like a financial debt, the technical debt incurs interest payments, which come in the form of the extra effort that we have to do in future development because of the quick and dirty design choice. We can choose to continue paying the interest, or we can pay down the principal by refactoring the quick and dirty design into the better design. Although it costs to pay down the principal, we gain by reduced interest payments in the future.

• ​http://martinfowler.com/bliki/TechnicalDebt.html

Also see

• Dissecting Technical Debt - ​http://www.infoq.com/news/2009/10/dissecting-technical-debt
• Overcoming slow problem solving due to increased knowledge of what might go wrong - ​link to the item in StackExchange