The Collaborative International Dictionary
Criticaster
Criticaster \Crit"ic*as`ter\ (kr[i^]t"[i^]k*[a^]s`t[~e]r), n. A contemptible or vicious critic.
The rancorous and reptile crew of poeticules, who
decompose into criticasters.
--Swinburne.
Wiktionary
criticaster
n. A petty or charlatan critic.