a copper-bottomed plan, agreement, or financial arrangement is completely safe.

She has a copper-bottomed contract with a very successful company. (always before noun)

• nothing but something
• nothing daunted
• nothing doing
• Nothing doing.
• nothing if not
• nothing if not something
• nothing less than
• nothing less than something
• nothing much
• nothing short of
• nothing short of something
• nothing to do with
• nothing to it
• nothing to sneeze at
• nothing to write home about
• Nothing ventured, nothing gained.
• not hold breath
• not hold liquor
• not hold water
• not hold your breath
• not hold your liquor
• not hurt a fly
• not if can help it
• not if you can help it
• not in a month of Sundays