Crossword clue: of, pertaining to, or conveying, preliminary instruction; introductory to any art or science; instructing beforehand.
2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).
Possible answers
a course that provides an introduction to an art or science (or to more advanced study generally)
Of, pertaining to, or conveying, preliminary instruction; introductory to any art or science; instructing beforehand.