“Knismesis and gargalesis are the scientific terms, coined in 1897 by psychologists G. Stanley Hall and Arthur Allin,[1] used to describe the two types of tickling. Knismesis refers to the light, feather-like type of tickling. This type of tickling generally does not induce laughter and is often accompanied by an itching sensation.[2] Gargalesis refers to harder, laughter-inducing tickling, and involves the repeated application of high pressure to sensitive areas.[2] This “heavy tickle” is often associated with play and laughter.”
Source: Wikipedia
