A rocking horse.
It means get that child to a doctor/psychiatrist ASAP!
I believe that it might be because when you are a baby your mom and dad hold you and rock you back and forth when you cried. I don't believe that all people rock back and forth when they cry though.
Can be...I am crazy.
Stand still.
Tourettes or autisum
A rocking horse
She rocks her whole body
when a river winds back and forth, it is called meandering
Moving back and forth in time is called time travel.
Reciprocating.
Assuming you mean back and forth from sideline to sideline or baseline to baseline, that would be called a suicide.
Because the river want to turn 180 degree.
Vibrations
Longitudinal or compression waves.
Longitudinal or compression waves.
Longitudinal or compression waves.
Longitudinal or compression waves.