thesaurusi

English

Alternative forms

• thesauri
• thesauruses

Noun

thesaurusi

1. (rare, nonstandard) plural of thesaurus
   • 1965, Pierre A. Rinfret, “Changing Population and Changing Demand”, in Financial Analysts Journal, volume 17, number 5, →JSTOR, page 75:

     In the closing weeks of 1959 and the early weeks of 1960, book dealers must have had a bonanza in selling thesaurusi.

   • 1999, Lynn Tooma with et al., Exploring the Bible, →ISBN, →OL, page 49:

     Gather a variety of dictionaries and thesaurusi written for middle-school students as well as adults.

   • 2004, Vincent Mary, “MeSH and Specialized Terminologies”, in MedInfo 2004, →ISBN, →OL, page 530:

     UMLS is an integration of several thesaurusi.

Usage notes

• This word is incorrectly formed. For masculine nouns in the nominative case of Latin’s second declension (of which thēsaurus is one), -us and -ī are singular and plural endings, respectively; one or the other attaches to the noun’s stem (thesaur-), depending on number: the plural ending does not concatenate as thesaur- + -us + -i = thesaurusi, but rather supplants the singular ending (-us) as thesaur- + -i = thesauri — thus forming the correct Latin nominative plural, which is also valid in English. Alternatively, in English, thesaurus, can be suffixed with the English plural suffix -es, to form another correct plural form of thesaurus, thesauruses. Thesaurusi is a rare error.