A gesture is a form of non-verbal communication in which visible bodily actions communicate particular messages, either in place of speech or together and in parallel with words.
Source: Boundless. “Movement and Gesture.” Boundless Communications. Boundless, 03 Jul. 2014. Retrieved 21 Jan. 2015 from https://www.boundless.com/communications/textbooks/boundless-communications-textbook/delivering-the-speech-12/components-of-effective-visual-delivery-65/movement-and-gesture-261-10649/