UK, 1839—jocular variant of ‘penny-a-liner’ (i.e., a journalist who was paid at the rate of a penny a line, a person who produced mediocre journalistic work) with the implication that such journalists fabricated falsehoods
1546—of little or no worth—here, ‘pudding’ refers to a sausage-like mass of seasoned minced meat, oatmeal, etc., stuffed into a prepared skin and boiled
USA, 1937—informative material presented in an entertaining way at working-meetings (and later at other types of gatherings) organised by Shell Oil Company—a blend of ‘information’ and ‘entertainment’
late 18th century, in the context of piracy: to walk along a plank placed over the side of a ship until one falls into the sea—hence, figuratively, early 19th century: to be forced to resign from one’s office or position
nonsense, rubbish—USA, first decade of the 20th century—probably a euphemism for the noun ‘bullshit’, with the noun ‘dust’ used in the sense of ‘rubbish’, ‘garbage’
1910: a cheap and common watch—hence (from 1922 onwards) used in various phrases referring to silliness, reliability/unreliability, erraticism, cheapness, funniness
refers to a person who is ignorant or dismissive of the hardships of others—alludes to the phrase “let them eat cake”, attributed to Marie Antoinette, wife of King of France Louis XVI
USA, 1950, as ‘shopping-bag stuffer’—an advertising leaflet or similar piece of promotional material handed out to shoppers or placed in shopping bags alongside goods purchased