Only people with an engineer title could be used as "engineers". However, some with competence and practical experience in an engineering field that do not need such a title, can nevertheless be employed to accomplish engineering jobs as "specialist", "assistant", "technologist" or "technician". Engineering is probably the broadest STEM fields. https://hectorw4pw2.blogsuperapp.com/30868668/the-fact-about-engineering-that-no-one-is-suggesting