Why did linguists choose 'Patient' (noun) to denote this Thematic Role?
THEMES and PATIENTS are rather similar, and not all linguists distinguish between these roles. A THEME typically moves from one location or one person to another, like the letter in (31). A PATIENT (or undergoer), like the window in (35), is physically affected by the verb’s action – so the window gets broken. A subject can also be a PATIENT, as with the flowers in (34): by wilting, the fl owers undergo a physical change of state, but they certainly don’t deliberately wilt, so that noun phrase is not the AGENT.
Maggie Tallerman, Understanding Syntax (2020 5 edn), p 49.
How's this sense of Semantic Role related to the lay 2021 English sense of 'patient', i.e. a "suffering, injured, or sick person under medical treatment"?
Why did linguisticians pick 'patient' to denote this Theta Role? Why not pick 'undergoer' that would be less ambiguous, polysemous, and thus less baffling, than 'patient'?