These are my personal interpretations of the following; I am very much aware whese are not necessarily a perfect fit with the dictionary definitions.

Leftist- Anyone slightly to the ideological left of the US democratic party, or who has finally learned to unlearn and shed the pejorative and damaging term "liberal" from their political identity, and can discuss politics like an adult.

Socialist- One who believes in common ownership of means of production, or who otherwise supports the ultimate end-goal of the abolishment of capitalism via whichever means they deem appropriate

Communist- A socialist who belives a socialist (and ultimately communist) society can only be achieved via revolutionary means, which may be violent in nature.

State- The geopolitical agglomeration of peoples within the otherwise imaginary construct known as a "border" and the hierachical entities (people and systems) that govern those peoples within that border. Maintains the the only legitmacy in the monoply of the use of force, known as "authority"

Praxis- Application of theory in the real world, such as a formation of a worker's party, performing mutual aid, organizing strike/protest action, overtherthowing the bourgeois state and installing a dictatorship of the proletariat to last in perpetuity until the lower stages of communism are achieved.

Tankie- a made up term that means nothing, but vaguely alludes to Marxist-Leninists-Maoists. Usually applied by people who don't know any actual MLs outside Stalin and company.