Thank you for being kind enough to recognize autocorrect causing problems.

I asked because it highlights who is causing leftist infighting by labeling people as tankies when said person disagrees with their points of view.

To answer your request, a liberal is someone that supports liberalist values. Liberalist values are ones that value individual rights over the rights of all people. Often, it's presented as "the right of the individual to X," not considering whether or not it actually helps all people equally or just a select few, and often it is benefitting only a select few. They employ a nonscientific approach to the social sciences (particularly political and socioeconomic sciences), prefer to function on what usually would seem to benefit themselves, and inso reject Marxist theory or theories built off of it such as Leninism while ignoring the historical evidence of it being the only successful threat to capitalism effective enough for capitalists to consider it a threat.

If you wanted a good starting point for identifying liberal values in ones ideologies, here's a solid starting point.