Keywords: duck (lower head)
Sign Definition
As a Noun
                                            1.  The movement of your head quickly downwards to avoid being seen or hit by something.
                                          
                                          
                                        As a Verb or Adjective
                                            1.  To move your head quickly downwards to avoid being seen or hit by something. English = duck, duck your head.
                                          
                                          
                                         
                  
                      