This answer seems wrong. I just checked with a native Italian speaker, who said that my answer ("the middle finger") is correct. "The medium" (in the "average" sense) should be "la media".
Il medio has a too many different translations: average, the middle, the middle finger, medium, etc., depending on context.
average = la media
the middle = la meta (with an accent on the / a)
the middle finger = il dito medio
medium = medio
the medium = il medio
do we mean "median" (one way of calculating an average) if so should it be acceptable. what are the technical words for mode, median etc?