Nouns

(n)intermediatea substance formed during a chemical process before the desired product is obtained

Verbs

(v)intercede, mediate, intermediate, liaise, arbitrateact between parties with a view to reconciling differences“He interceded in the family dispute”, “He mediated a settlement”

Adjectives

(a)intermediatelying between two extremes in time or space or state“going from sitting to standing without intermediate pushes with the hands”, “intermediate stages in a process”, “intermediate stops on the route”, “an intermediate range plane”
(s)average, intermediate, mediumaround the middle of a scale of evaluation“an orange of average size”, “intermediate capacity”, “medium bombers”