whippersnapper
From Longman Dictionary of Contemporary EnglishRelated topics: Youthwhippersnapperwhip‧per‧snap‧per /ˈwɪpəˌsnæpə $ ˈwɪpərˌsnæpər/ noun [countable] old-fashionedSSYRUDE/IMPOLITE a young person who is too confident and does not show enough respect to older peopleExamples from the Corpuswhippersnapper• An older Tony Gwynn must compete only with that whippersnapper and a young Dave Winfield with an aversion to the right-field wall.Origin whippersnapper (1600-1700) Probably from snipper-snapper “whippersnapper” ((16-19 centuries)), probably from snip + snap