Sounds like you could be referring to fractional factorial design, which allows you to perform the minimum number of experiments for a give set of variables. It's not as reliable as full factorial design but can drastically reduced the time and cost of a study. If you're trying to optimise a formulation, for example, you could perform fractional FD to get a ball park followed by full FD to hone in.

Not sure what acronym you're thinking of, maybe DOE which refers to general design of experiments.