Shell roof definitions

Shellproof

1) Bombproof 2) Invulnerable
Found on https://www.crosswordclues.com/clue/shellproof

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Shellproof

• (a.) Capable of resisting bombs or other shells; bombproof.
Found on http://thinkexist.com/dictionary/meaning/shellproof/

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Shellproof

Shell'proof` adjective Capable of resisting bombs or other shells; bombproof.
Found on http://www.encyclo.co.uk/webster/S/86

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