Meaning of -ING in English

[-ing] n suffix [ME, fr. OE -ung, -ing, suffix forming nouns from verbs; akin to OHG -ung, suffix forming nouns from verbs] 1: action or process "running" "sleeping": instance of an action or process "a meeting"

2. a: product or result of an action or process "an engraving"--often in pl. "earnings" b: something used in an action or process "a bed covering" "the lining of a coat"

3: action or process connected with (a specified thing) "boating"

4: something connected with, consisting of, or used in making (a specified thing) "scaffolding" "shirting"

5: something related to (a specified concept) "offing"

[2]-ing n suffix [ME, fr. OE -ing, -ung; akin to OHG -ing one of a (specified) kind]: one of a (specified) kind "sweeting" [3]-ing vb suffix or adj suffix [ME, prob. fr. [1]-ing]--used to form the present participle "sailing" and sometimes to form an adjective resembling a present participle but not derived from a verb "swashbuckling" usage Though the pronunciation of -ing with the consonant /n/, misleadingly referred to as "dropping the g," is often deprecated, this pronunciation is frequently heard. It is not known for certain why the Middle English present participle ending -ende was replaced by -ing. Analogy with the earlier noun suffix -ing prob. had something to do with it. In early Modern English, present participles were regularly formed with -ing. Evidence also shows that some speakers used /in/ and by the 18th century this pronunciation became widespread. Though teachers (with some success) campaigned against it, /in/ remained a feature of the speech of many of the best speakers in Britain and the U.S. well into this century. It has by now lost its respectability, at least when attention is drawn to it, but throughout the U.S. it persists largely unnoticed and in some dialects it predominates over /ing/.

Merriam-Webster English vocab.      Английский словарь Merriam Webster.