Noun. Plural "apostrophies". A prize-winning apostrophe error.
An apostrophe added to a plural word ("apostrophe's" is wrong), or missing from a possessive word ("Johns car" is wrong) or other similar error, in a public or other glaringly obvious place - such as a broadsheet newspaper headline, in financial terms & conditions, or a celebrity's tattoo.
Each of these, if published, could be classed as an apostrophy:
ARGIE'S INVADE FALKLANDS
It is the Companys responsibility to...
Your the one for me