Dusting and vacuuming... In doing this with my husband I learned EXACTLY why guys say something is clean when us ladies say that it isn't.
To men... picking up stuff is cleaning...
To women... Its picking up, dusting, sweeping, vacuuming, polishing, wiping, scrubbing, shining, you know.... cleaning.
In recognizing this if you talk to my husband he will tell you that the MOST SUBJECTIVE WORD in the English language is the word "clean"