Based on the number of words per meaning across the Indo-European Swadesh list, Pagel et al. (2007) suggest that frequency of use is a general mechanism of linguistic evolution. We test this claim using within-language change. From the IDS (Key & Comrie 2015) we compiled a comparative word list of 1,147 cognate pairs for Classical Latin and Modern Spanish, and 1,231 cognate pairs for Classical and Modern Greek. We scored the amount of change for each cognate pair in the two language histories according to a novel 6-point scale reflecting increasing levels of change from regular sound change to external borrowing. We find a weak negative correlation between frequency of use and lexical change for both the Latin-Spanish and Classical-Modern Greek language developments, but post hoc tests reveal that low frequency of use of borrowed words drive these patterns, casting some doubt on frequency of use as a general mechanism of language change.