Perhaps 
s/((((((((((((v)?a)?c)?[ai])?t)?i)?o)?n)?\.)?m)?s)?g)//;

[download]
is what you're looking for? A suffix of any length? You can make all of those open parens into non-capturing ones if you want. Update: with the a-or-i spelling variation (allowing "vacition.msg").
The PerlMonk tr/// Advocate

In reply to Re: Rewrite a Regular Expression to be easier to understand by Roy Johnson
in thread Rewrite a Regular Expression to be easier to understand by Anonymous Monk

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