If you've ever heard George Carlin's famous "Seven Dirty Words" you can't say on TV, you can safely avoid using all seven in your subject lines. They will definitely get you blocked.
Here is a list of 100 more that you should avoid using as well:
Top 100 words NOT to use in your subject lines:
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all words that relate to sex or pornography
all words that related to cures or medication
amazing
anything that looks like you are YELLING
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as seen
as seen on Oprah
as seen on TV
avoid
be your own boss
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cialis
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collect
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consolidate
contains $$$
contains word "ad"
credit
Dear Friend
discount
don't delete
double your anything
double your income
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earn
earn $
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eliminate debt
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for you
FREE
free
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friend
g a p p y t e x t
get
get out of debt
hello
herbal
hidden
home based
hot
information you requested
instant
levitra
life insurance
limited time
loans
lose
lose weight
lower your mortgage rate
lowest insurance rates
make money
medicine
mortgage
multi level marketing
notspam
now only
numerical digits at the end
offer
online degree
online marketing
online pharmacy
only
open
opportunity
promised you
refinance
removes
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serious cash
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stop or stops
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your family
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