In the glosses of the analyzable words full forms were used with their translations in English. No abbreviations were used, either from the Leipzig set of glossing rules or other.

In order to determine the age of a loanword the following criteria were used. We verified if the Spanish loanwords already were attested by Urbano in his Arte breve de la lengua Otomi y vocabulario trilingüe from 1605. And we asked several elder native speakers of Otomí if the Spanish loanwords were borrowed after around 1950 or if they already were used before that year. So we classified the loanwords in three groups:
a. Spanish words attested by Urbano
b. Pre-modern words borrowed before around 1950
c. Modern words borrowed after around 1950

According to the degree of probability that a specific word is a loanword, words might be classified in five types (0. no evidence for borrowing; 1. very little for borrowing; 2. perhaps borrowed; 3. probably borrowed; 4. clearly borrowed). Because of our familiarity with the Otomí language for most of the 1459 entries in the LWT vocabulary it was easy to determine if a word was a loanword or not, even for old loanwords such as anxe, ata, badu, xabo, xebo, etc., which are more adjusted to the phonological patterns of Otomí than the recent loanwords. So almost all the entries of our wordlist belong to type 0 (no evidence for borrowing) or type 4 (clearly borrowed).

- Most of the observations stem from field work done by Hekking. The observations in the database have been checked intensively with several native speakers of Otomí.
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