The phrase "wiggle room" gives 2 million results on Google. "Wriggle room" gives 140 thousand, suggesting that both phrases are valid English.
Google N-grams seems to back this theory up too.
And what's more, it seems to suggest that both phrases first appeared at around the same time.
The dictionary definition of wriggle seems to be subtly different from wiggle– Wriggling implies an intention to move somewhere, whereas wiggling does not.
So, what — if anything — is the difference between the two phrases? And is there any evidence that one came before the other?
Best Answer
In a 5 December 2004 NYT column, William Safire commented on the wriggle room vs wiggle room controversy, and wrote that “wiggle room predominates in current usage by more than 14 to 1”. The ratio appears to be still about 14 to 1, nine years later. (Google shows 2,080,000 and 147,000 results at the moment on my computer, a ratio of 14.15 to 1.)
Safire discussed wiggle room in a column in the early 1980's. In his 2004 column, he remarked:
Note that ngrams for wiggle room,wriggle room shows instances of wiggle room occurring in the 1890's, and wriggle room not appearing until the 1960's. The ngrams shown in the question, with its 1945 starting date, is misleading with respect to dates of first usage.
A 2011 thread in the Eggcorn Forum quoted from Safire's 2004 column, and went on to point out:
A 2004 straightdope.com thread suggests, and I think refutes, a “pondian” difference in usage (ie, British English versus American). Among other items it includes a chart based on counts of web pages containing instances of color or colour along with wiggle room or wriggle room. If colour is a good indicator of BE usage, then the ratio of wiggle room over wriggle room is similar in both BE and AE: