Rubicon Rubicon /ˈruːbɪkɔn/

noun

1. A line that when crossed permits of no return and typically results in irrevocable commitment  ( point of no return , Rubicon )
   a line that when crossed permits of no return and typically results in irrevocable commitment
   
2. The boundary in ancient times between Italy and Gaul; Caesar's crossing it with his army in 49 BC was an act of war  ( Rubicon )
   the boundary in ancient times between Italy and Gaul; Caesar's crossing it with his army in 49 BC was an act of war
    Crossing the Rubicon was a significant event in history.
   Crossing the Rubicon was a significant event in history.
   
   

 grownup grownup /ˈgroʊˌnəp/

adjective

1. (of animals) fully developed  ( big , fully grown , grownup , adult , full-grown , grown )
   (of animals) fully developed
    An adult animal
   an adult animal
    A grown woman
   a grown woman
   

noun

1. () A fully developed person from maturity onward  ( grownup , adult )
   a fully developed person from maturity onward
    As an adult, it's important to take responsibility for your actions
   As an adult, it's important to take responsibility for your actions
   
   

 Mickey Charles Mantle Mickey Charles Mantle /ˈmɪki ˈtʃɑrlz ˈmæntəl/

noun

1. United States baseball player (1931-1997)  ( Mantle , Mickey Charles Mantle , Mickey Mantle )
   United States baseball player (1931-1997)
   
   

 critter critter /ˈkrɪtɝ/

noun

1. A regional term for 'creature' (especially for domestic animals)  ( critter )
   a regional term for 'creature' (especially for domestic animals)
    Every night, a little critter visits our backyard, nibbling on leftover food.
   Every night, a little critter visits our backyard, nibbling on leftover food.