kidding

The verb 'to kid' originated in the 19th century from the noun 'kid', which entered English from Old Norse 'kið', referring specifically to a young goat. The semantic leap from 'young goat' to 'teasing' or 'playful deception' is thought to be influenced by the playful, frisky behavior associated with young animals. The addition of the present participle suffix '-ing', a native English grammatical marker from Old English '-ende', transforms the verb into its continuous form, describing the ongoing act of playful jesting. Thus, 'kidding' literally means "engaging in the act of playful jest," a meaning that evolved metaphorically from observations of animal behavior.

Structure: kid (young goat/child) + ing (present participle suffix) - kid: From Old Norse 'kið', meaning a young goat. Its sense extended to 'child' in informal English. In this word, it carries the core meaning of playful jest. - ing: A suffix of Old English origin, used to form the present participle of verbs, indicating an ongoing action or state.