Lexical set

A lexical set is a group of words that share a similar phonological feature.

The Standard Lexical Sets for English introduced by John C. Wells in Accents of English are in wide usage. Wells defined each lexical set on the basis of the pronunciation of words in two reference accents, which he calls RP and GenAm.

Wells classifies words of the English language into 24 lexical sets on the basis of the pronunciation of the vowel of their stressed syllable in the two reference accents. Each lexical set is named after a representative keyword, as follows:

* not followed by /r/

For example, the word rod is pronounced /rɒd/ in RP and /rɑd/ in GenAm. It therefore belongs in the LOT lexical set. Weary is pronounced /ˈwɪərɪ/ in RP and /ˈwɪri/ in GenAm, and thus belongs in the NEAR lexical set.

Some words of the English language do not belong to any lexical set. For example, the a in the stressed syllable of tomato is pronounced /ɑː/ in RP, and /eɪ/ in GenAm, a combination which is very unusual, and is not covered by any of the 24 lexical sets above.

Wells explains his choice of keywords ("kit", "fleece", etc.) as follows:

The keywords have been chosen in such a way that clarity is maximized: whatever accent of English they are spoken in, they can hardly be mistaken for other words. Although fleece is not the commonest of words, it cannot be mistaken for a word with some other vowel; whereas beat, say, if we had chosen it instead, would have been subject to the drawback that one man's pronunciation of beat may sound like another's pronunciation of bait or bit.

Wherever possible, the keywords end in a voiceless alveolar or dental consonant.

Wells also describes three sets of words based on their word-final unstressed vowels. Although not included in the standard 24 lexical sets, these "have indexical and diagnostic value in distinguishing accents".

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