Female friend on WhatsApp this evening, to whom I reminded the definition of sarcasm while explaining something, said she didn't have time to worry about knowing the definition of words because she is a "subjective person".
The dictionary defines subjectivity by: dependent on the mind or on an individual's perception for its existence. ( And by extension a subjective person is somebody who pays (or likes paying) attention to the subjective aspect of things. )
So according to the definition, a subjective person likes considering how various mental states (possible their own mental state) give existence to things (concrete, abstract, real or imaginary). For instance a subjective person might consider that there is beauty in the moonlight. The existence of "beauty" in that context depends on the person's mind's state.
That being said, subjective people can be very accurate with their words. They might (and should) be able to clearly define what the moon is and what beauty is. They should be able to clearly communicate the nature of the thing they postulate the existence of, to people who are willing to listen but might not share their subjective experience.
When people say "I can't be bothered with precise definitions for the words I use because I am a subjective person", what they really say is "I am mentally lazy and I don't even respect you enough to make the minimum effort required for you to understand me".