I was taught that "ball-point pen" = compound noun, but "ball-point" is NOT an adjective because it doesn't pass the primary tests for an adjective (has adjective-making morpheme, can have/ be made comparative or superlative, can be qualified, and fits the frame sentence "the ___ man seems very ___").
And then I was taught the royal order of adjectives: "determiner, observation/opinion, size........, qualifier (often a noun), noun." And the example of qualifier, then noun, was: "ball-point pen." So doesn't "ball-point" = qualifier = adjective?