Tispt
The sound you make when you go to sit down but the chair is farther away from your ass than you anticipated, or not even there, so you do a full falling spasm.
Person 1: 'Oh look, a chair.'
*Starts to sit down*
*Person 2 pulls the chair away*
Person 1: 'TISPT.' *falls over*
Person 2: 'Ahahahahaha.'
*Starts to sit down*
*Person 2 pulls the chair away*
Person 1: 'TISPT.' *falls over*
Person 2: 'Ahahahahaha.'