How did “turkey” become a derogatory term? The turkey, after all, is not the most ungainly of God's creatures, not if you contemplate anteaters or right-wing talk show hosts.
The answer, as is the case for many such American slang usages, lies buried in those library stacks that host a collection of the back issues of Variety, the self-proclaimed bible of showbiz. Here’s the plot:
In the 1920s, Broadway was booming. It cost a great deal less to mount a show in those days, and there were far more theaters on or near the Great White Way than there are today. In 1928, the peak year before the Crash, nearly 300 shows opened on Broadway.
And a lot of them closed very quickly. However, the one way that producers could ensure their shows would last at least five or six weeks—long enough to make their money back and maybe a little more—was to open their shows around Thanksgiving. Then as now, the show-going public would swell during the holiday season, as tourists and locals viewed the weeks between Thanksgiving and New Year's as the show-going time of the year.
Not surprisingly, this meant that Variety’s theater critics, who had to shlep to and review every last one of those shows, were subjected to an inordinate number of real lulus. When a producer had sunk his or someone’s money into what he realized was a stinker of a play or musical, the only way he could emerge financially unscathed was to open that show around Thanksgiving.
Soon, Variety's critics coined a name for such shows: turkeys. The rest, as they say, is history.