In Marxist terms, the working class and the proletariat are conflated. Marx sometimes called the working class "the wage-working class" and then, synonymously, "the working class". Tenant farmers are usually distinguished due to a different class interest, which is to say that their primary goal (historically, along with other kinds of peasant) has been to obtain the land they work on, which Marxists usually describe as a petty bourgeois ambition. This emerges due to their relation to production, where they experience essentially the full gamut of the production of crops through their labor, usually only being alienated by a lack of ownership of the land itself and maybe some of the equipment. The development of uniting these peasant interests of land reform with proletarian interests in the cities was one of the key factors in successful revolutions led by MLs. After the revolution, this then immediately led to a need to deal with the petty bourgeois interests of peasany landowners, usually by limiting the amount of farming land that anyone other than the state could own and sometimes needing to immediately fight a small war against peasants that revolted due to their interests clashing with those of the industrial workers and the program of the revolutionary party(ies).

Apologies if much of this is review, just adding context in the hope that it is explanatory of my meaning.