Epenthesis

Epenthesis – the word is pronounced with the stress on the second syllable, IPA: / ɛ 'pɛn θɪ sɪs/ – is the addition of letters or sounds to a word, especially the insertion of letters or sounds into the middle of a word, e.g., the ‘e’ inserted before the ‘s’ of the plural in words ending -sh, -ch, -s, -x , -z (as in ‘bushes’, ‘churches’, ‘classes’, ‘boxes’, ‘fezzes’) or the shwa which some native English speakers (e.g., in Northern Ireland) introduce between the ‘l’ and ‘m’ of such words as ‘film’ and ‘elm’.

Epenthesis is the opposite of syncope, i.e., the omission of one or more letters from the written form of a word or of one or more sounds from a spoken word.

Epenthesis typically occurs, for the sake of convenience or ease of diction, when native speakers find certain combinations of sounds difficult to pronounce – for example:

when the short ‘a’ of the indefinite article immediately precedes a word beginning with a vowel, an epenthetical ‘n’ is added to the indefinite article, as with, e.g., ‘an apple’, ‘an egg’, ‘an improvement’, ‘an orchid’, ‘an ugly duckling’;

in some words in which the consonantal combination ‘ml’ would be difficult to pronounce an epenthetical ‘b’ has been inserted between the two letters, as in ‘thimble’ (from Old English thymel (‘thumbstall’)), ‘ramble’ (probably from Middle Dutch rammelen (‘to roam’)), ‘’humble’, (originally from Latin humilis), ‘crumble’ (compare Low German krömeln and Dutch kruimelen), and ‘stumble’ (related to Norwegian stumla and Danish dialect stumle).

Etymological note: Epenthesis is a transliteration of the Greek ἐπένθεσις (epenthesis, ‘insertion’), itself a compound formed from the prepositions ἐπί (epi, ‘on’, ‘in addition’) and ἐν (en, ‘in’), and the noun θέσις (thesis, ‘placing’). One of the uses of the Greek word anticipates that of its English descendant.