Here's what rhymes with oncountered.
                        
                        
                    
                                countered  encountered  Words that almost rhyme with oncountered
foundered  floundered  downward  coward  cowered  cowherd  cowbird  powdered  powered  southward  scoured  showered  towered  soured  glowered  dowered  empowered  flowered  embowered  devoured  overpowered  deflowered