This paper reports on a collaborative quantitative study of loanwords in 41 languages, aimed at identifying meanings and groups of meanings that are borrowing-resistant. We find that nouns are more borrowable than adjectives or verbs, that content words are more borrowable than function words, and that different semantic fields also show different proportions of loanwords. Several issues arise when one tries to establish a list of the most borrowing-resistant meanings: Our data include degrees of likelihood of borrowing, not all meanings have counterparts in all languages, many words are compounds or derivatives and hence almost by definition non-loanwords. We also have data on the age of words. There are thus multiple factors that play a role, and we propose a way of combining the factors to yield a new 100-item list of basic vocabulary, called the Leipzig-Jakarta list.