Why do psychologists say “patient” and not “client”?
The word “patient” comes from the Latin “patior”, which means “to suffer”. Given that the person that comes to consult a psychologist is someone who suffers emotionally and wishes to receive help, it makes sense for that person to be a “patient”.
“Patior” also means “to experience, to wait”. The therapeutic process implies experiencing certain inner situations and also knowing how to wait so that change can take place, thus the word “patient” acquires its full meaning.
The word “client” refers to a commercial transaction, which is certainly the case between a psychologist and a patient because the latter pays for a service, but it would be very reductionist to use this term since it ignores the reason for which the person wishes to receive that service.
Therefore, it would make as much sense to call “client” the person that goes to see a psychologist as it would to call “client” the person that goes to see a doctor; in both cases the person that consults suffers and is seeking help to relieve the suffering.