Definition from Nolo’s Plain-English Law Dictionary

The process of acquiring misspellings of a domain name in the hopes of catching and exploiting traffic intended for another website. For example, a typosquatter might purchase domain names such as www.lnadsend.com and www.landswnd.com and then demand money for referring customers under the Land's End affiliate program. Typosquatting is a variation of cybersquatting, an illegal practice in which a domain name is acquired in bad faith.

Definition provided by Nolo’s Plain-English Law Dictionary.