suffix a doer (of the verb). Jocular repetitious use of the agent suffix '-er'. Normally only one 'er' is used for a compound verb, thus 'wash up' becomes 'washer-up'. Then, added to both parts of the compound, 'washer-upper'. And sometimes, for comic effect, with a third '-er' added to the new compound as a whole, 'washer-upperer'. This last especially used by children AUSTRALIA, 1964