cling: [OE] The basic underlying sense of cling seems to be ‘stick, adhere’, but surviving records of the word in Old English reveal it only in the more specialized senses ‘congeal’ or ‘shrivel’ (the notion being that loss of moisture causes something to contract upon itself or adhere more closely to a surface). It is not really until the late 13th century that the more familiar ‘adhere’ (as in ‘a wet shirt clinging to someone’s back’) begins to show itself, and no hint that ‘clinging’ is something a human being can do with his or her arms emerges before the early 17th century.
The word goes back to a prehistoric Germanic base *klingg-, whose variant *klengk- is the source of English clench [13] and clinch [16]. => clench, clinch[cling etymology, cling origin, 英语词源]