A portmanteau of slacker and activism) is a pejorative term for “feel-good” measures in support of an issue or social cause. Slacktivism is showing support for a cause with the main purpose of boosting the egos of participants in the movement. The action may have little effect other than to make the person doing it feel satisfied that they have contributed. Slactivism is often a form of “virtue signalling”. The underlying assumption being promoted by the term is that these low-cost efforts substitute for more substantive actions rather than supplementing them, although this assumption has been criticized.

-Wikipedia