Attributions

Word list: ENABLE

Enhanced North American Benchmark Lexicon, public domain. Copy from the dolph/dictionary repository.

Definitions: WordNet

Short definitions are taken from the WordNet 3.1 database files (distributed in the wordnet-db package) and shortened. WordNet license and notice:

WordNet Release 3.0

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George A. Miller (1995). WordNet: A Lexical Database for English. Communications of the ACM, 38(11), 39-41.

Word frequencies: SUBTLEX-US

Common-word ranking uses SUBTLEX-US by Marc Brysbaert and Boris New, a freely available word-frequency list derived from American film and TV subtitles, via the subtlex-word-frequencies package (ISC). Brysbaert, M. & New, B. (2009). Moving beyond Kučera and Francis. Behavior Research Methods, 41(4), 977-990.

Offensive-word filter

“List of Dirty, Naughty, Obscene, and Otherwise Bad Words” by Shutterstock contributors, CC BY 4.0, via the naughty-words package. Used only to hide words; the list itself is not shown.

Fonts

Atkinson Hyperlegible (Braille Institute) and Zilla Slab (Mozilla), both under the SIL Open Font License.