Like every specialised field, program evaluation has developed particular terms to represent its own realities and to facilitate communication among professionals of the area.
In program evaluation, "design" does not refer to visually pleasing objects but rather to the structure of one's proof; "beta" is not a software version number, it's a statistical coefficient; "classification" generally does not affect one's pay scale since it is a means of measuring objects; "meta" is not the Megachannel Extra-Terrestrial Array but rather the prefix of "meta-evaluation".
Here is a very incomplete list of glossaries of program evaluation terms. If you know of other ones, please let us know.