separate out the men from the boys

Meaning

1. separate / sort out the men from the boys

   to show or prove who is brave, skilful, etc. and who is not

From the same entry

• as one man
• be man
• be man enough
• every man for himself
• make a man of
• a man about town
• man and boy
• the man in the street
• a man of God cloth
• the man of the match
• a man of the people
• man's best friend