DSP is the short form of direct support professional. In this field it means the person paid to provide community support to someone with an intellectual or developmental disability. The three letters are how the job appears in a help-wanted ad, a union flier, a rate study, and a state budget footnote.
The acronym is also a definition fight. A bill can say DSP and then limit the word to staff billed under a particular waiver, or to employees of a provider agency, or to workers who are not family members. When that happens, the acronym is narrower than the profession. Reading the definition section matters more than the headline.
The same three letters name unrelated things, including digital signal processing and a demand-side advertising platform. Pages about those topics are not about this workforce. In disability services, DSP almost always means the direct support job. If a document means something else, it will say so in the first paragraph or it is using the wrong shorthand.
Surveys and recognition campaigns use the acronym on purpose. National Core Indicators asks agencies about DSP wages, vacancies, and turnover. ANCOR, the national provider association, organizes a recognition week around the job. Neither of those uses is a wage increase. They are how the field talks about the workforce in public.
If you are trying to learn the work, start with the full title. If you are reading a budget, a rate memo, or a staffing chart, DSP is the word they used, and the next question is who the document counts.
Staff themselves use the acronym more than the full title. A recognition week, a staffing chart, and a union leaflet will all say DSP and mean this job. The full phrase belongs in the definition, in training standards, and anywhere a reader might confuse the letters with another industry.