A doddle is any endeavour that can be accomplished easily without any great effort. It has been used in this way in Britain and other English-speaking countries (excluding North America) since the 1930s. The exact origin is uncertain. The verb, to doddle, rarely heard these days, dates from the mid-17th century and means to nod or shake the head. From the mid-18th century, it meant to toddle or dawdle along i.e. a slow, easy walk and this may be the origin of its current meaning signifying anything that is easy. See also walk/stroll in the park and cakewalk.