The study focuses on language aggression as it is enacted in virtual professional communities. With the aim to reveal the dominant forms and mechanisms of aggression in the virtual environment, the authors explore data retrieved from Russian social media. Theoretically, the paper is informed by social identity theory and linguistic pragmatics. Adopting a methodology that draws on an inferential model of communication, the study analyses aggressive utterances and their meanings in situational contexts. The findings distinguish between two principal forms of aggression: insulting aggression and aggression of exclusion. Although both perform the function of social control, they differ in terms of triggering situations, pragmatic mechanisms as well as linguistic resources employed. Insulting aggression makes use of dehumanising, negative evaluation, blaming, social deixis, ‘reductio ad absurdum’ and references to one’s emotional involvement in the situation of conflict. Such mechanisms are enacted through the linguistic tools that convey the semantics of aggression more or less directly. These include pejoratives, depreciative epithets, colloquialisms, informal expressions, lexemes with semantics of emotional state, imperatives, means of deontic modality and a shift in using polite/impolite forms of address. On the contrary, aggression of exclusion involves meanings that require inferential efforts of the recipient. The interplay between literal meanings of speech acts and the underlying intentions results in conversational implicatures. Exclusion is manifested through drawing a boundary between ‘us’ and ‘them’, terminating a conversation, talking about somebody present in the third person. Its linguistic forms comprise lexemes with semantics of exclusion, lexis with negative connotation, interjections, and irony.