Wiktionary
n. A demonstration in opposition to another demonstration
WordNet
n. a demonstration held in opposition to another demonstration; "supporters of the president organized a counterdemonstration in his support"
Usage examples of "counterdemonstration".
In the few months since Emperor Onrad's declaration of war over the League's attack on Fluvanna, counterdemonstrations had grown apace until the number of loyal citizens often matched the CIGAs they opposed.
But a closer look revealed that their ranks were noticeably thinner than only a month previously—and a nearby counterdemonstration loomed like an ominous storm nearly ready to break over their heads.
Even if minority interest groups didn't organize counterdemonstrations, the Neumen had never been popular with the general public, who still venerated the superhuman Owen Deathstalker and his companions, and saw Neumen propaganda as an attack on their heroes.