Terminology is not well defined.
The problem is that the terminology in our field is loosely defined. The answer to your question might just be 'design'.
The different design terminologies varies by the specific context and process that they're used for. There is a debate about the meaning of terms and not all academic authors and practitioners agree with each other on the definitions.
Often times you can use several design terminologies for describing the same design process, and they can all will be valid.
So here I will list the ones that I think are relevant to your question:
Ergonomics / Human Factors
ISO 26800:2011 abstract presents the general ergonomics approach and specifies
basic ergonomics principles and concepts. These are applicable to the
design and evaluation of tasks, jobs, products, tools, equipment,
systems, organizations, services, facilities and environments, in
order to make them compatible with the characteristics, the needs and
values, and the abilities and limitations of people.
ISO 26800:2011. Scientific discipline concerned with the understanding of interactions
among human and other elements of a system, and the profession that
applies theory, principles, data and methods to design in order to
optimize human well-being and overall system performance
User Experience design
User Experience (UX) is also called experience design. UX design has many definitions but Don Norman was the first one to coin the term:
“I invented the term because I thought human interface and usability
were too narrow. I wanted to cover all aspects of the person’s
experience with the system including industrial design, graphics, the
interface, the physical interaction, and the manual. Since then the
term has spread widely, so much so that it is starting to lose it’s
meaning… user experience, human centered design, usability; all those
things, even affordances. They just sort of entered the vocabulary and
no longer have any special meaning. People use them often without
having any idea why, what the word means, its origin, history, or what
it’s about.”
Video of Don Norman explaining what is User Experience.
Dan Saffer has a book about interaction design and he classifies the disciplines like this:

Human-centered design
ISO 9241:210
Human-centred design is an approach to interactive systems development
that aims to make systems usable and useful by focusing on the users,
their needs and requirements, and by applying human
factors/ergonomics, and usability knowledge and techniques. This
approach enhances effectiveness and efficiency, improves human
well-being, user satisfaction, accessibility and sustainability; and
counteracts possible adverse effects of use on human health, safety
and performance.
Remember that the term system may not only mean a computer system or some other technological meaning, but can represent a system of processes supporting certain activity. For example for pedestrians have a system. It should have signage, lights, sidewalks, etc. This can be said that it is pedestrian system, just like the road system.
Conclusion
Possible terminologies for 'real life' user experience design that are safe to use, in my opinion, are but not limited to:
- ergonomics,
- human-centered design,
- (user) experience design,
- interaction design.