The AusTraits Plant Dictionary (APD) is the most complete formal vocabulary for ecological plant trait concepts, offering a resource for all researchers seeking semantically clear, well-defined plant trait definitions to apply to other datasets or reuse in other vocabularies. Without formal trait concepts, distinct datasets cannot be linked, limiting their reuse. The trait concepts were initially informal definitions required to compile the AusTraits database, a large, open-source, harmonised database of Australian plant trait data. Having a formal vocabulary of trait concepts is essential for the interpretation of the trait values within AusTraits, necessitating the transformation of the initial resource into a formal vocabulary, output in both human-friendly and machine-readable formats. This required three core steps, 1) Review of all trait concepts, trait definitions, and allowable categorical trait values; 2) Addition of metadata to each trait concept; 3) Building the trait dictionary into an rdf representation with resolvable URI's for each trait concept and categorical trait value. Metadata for each trait include a trait label, trait definition, units, allowable ranges (for numeric traits), allowable values (for categorical traits), structure measured, characteristic measured, keywords, references, reviewers, and links to identical/similar/related concepts in other trait dictionaries and databases. R scripts were developed to build the rdf representation from spreadsheets, offering a transparent, reproducible workflow that is intuitive to most ecology researchers and allowing new traits to easily be added to the vocabulary. Version note Corrects a formatting error in the original presentation file introduced during file conversion.