Smooth vb smoothed smoothing smooths also smoothes.
In the case of the Merriam-Webster's Collegiate Dictionary series, the Tenth Edition (1994) begins its entry for the verb smooth as follows: In seeking possible causes for the shift, I've looked at a number of dictionaries.
Simple Google searches for the two words yield about 2.82 million matches for smooths and about 4.59 million matches for smoothes. Ngram shows the two frequency lines crossing in 2002. I am interested in the rapid rise (since about 1993) in frequency of the spelling smoothes as against smooths.Īn Ngram Viewer graph tracking the frequency of usage of the two words from 1800 to 2005 shows remarkably stable levels of usage for both smooths and smoothes for about 150 years (1844 to 1993) but then it shows smoothes beginning a sharp ascent and smooths declining significantly.
