I was commenting on brochure or piece of paper one of the members was designing. I type in flyer but wondered if I should have used flier.
Here is what I found.
If you live beyond the gold old United States, there is little or no difference between flyer and flier. It appears the two terms are interchangeable. The non-U.S. users seem to prefer the flyer with and “er_ by about two to one.
Those of us living in American writers are prone to use flyer for small handbills or leaflet and flier for people and things that fly. In many cases, the trend is that the two words can be used interchangeably according The Grammarist.com
To confuse the issued a somewhat slangy use of flier is to do something in a reckless or speculative manner.
When it comes to describing the handbills/advertisements ,The Associated Press (an American organization), recommends “flier,” and The Economist (a British publication), which recommends “flyer.” Since I write for a newspaper, I go by the AP rules.