-ing(1)   suffix forming gerunds and nouns from verbs (or occas. from
             nouns), denoting: 1 a the verbal action or its result (asking;
             carving; fighting; learning). b the verbal action as described
             or classified in some way (tough going). 2 material used for or
             associated with a process etc. (piping; washing). 3 an
             occupation or event (banking; wedding). 4 a set or arrangement
             of (colouring; feathering). [OE -ung, -ing f. Gmc]

    -ing(2)   suffix 1 forming the present participle of verbs (asking;
             fighting), often as adjectives (charming; strapping). 2 forming
             adjectives from nouns (hulking) and verbs (balding). [ME alt.
             of OE -ende, later - inde]

    -ing(3)   suffix forming nouns meaning 'one belonging to' or 'one having
             the quality of', surviving esp. in names of coins and fractional
             parts (farthing; gelding; riding). [OE f. Gmc]


From the OED.


A