stretch - (something) out to greater or fullest length: Stretch your arm. extend - Cause to cover a larger area; make longer or wider. Please extend the due date to 48 hours from acceptance. expand - Become or make larger or more extensive. The company tended to hire more workers or expand when the economy improved. Although extend and expand can be used interchangeably in some contexts, extend applies to things that are being stretched out, while expand applies to things that are spread out. One implies length; the other area. If you extend your arm, for example, you stretch it out, making it longer. If your waist expands, it’s getting larger. As a business expands, or gets larger, it may extend its opening hours. Extend comes from a word meaning “to stretch out, lengthen.” (Latin extendere, “stretch out,” from ex- “out” + tendere, “to stretch.”)