Prefix talking about a gland, like in adenoma and adenopathy. Through the Greek aden definition initially "an acorn" and later "a gland" in the form of an acorn. Before a vowel, adeno- becomes aden-, as in adenitis (inflammation of a gland).
incorporating types of the Greek word for gland; -- used in words concerning the construction, conditions, etc., regarding the glands.
incorporating kinds of the Greek term for gland; -- found in terms regarding the construction, conditions, etc., associated with the glands.