the word 'teddy' originates from the nickname of theodore roosevelt, the 26th president of the united states. the connection to the toy bear arose from a 1902 political cartoon depicting roosevelt refusing to shoot a bear cub, an event which inspired a toy maker to create a stuffed "teddy's bear." the term was quickly commercialized and shortened to "teddy bear," with "teddy" eventually becoming a generic term for any soft toy bear. the use for a type of women's undergarment emerged later in the 20th century, likely influenced by the soft, comfortable, and sometimes playful connotations of the word.

the word is a proper noun converted into a common noun. it does not contain separable, productive morphemes in modern english.