Syllabic compression (also called syncope) is the loss of a mid-word unstressed syllable when saying a word. It most commonly occurs in high-frequency words when a syllabic consonant such as a 'syllabic l' /əl/, 'syllabic n' /ən/, or an unstressed 'schwa+r' /ɚ/ becomes a regular consonant (a syllabic consonant is a consonant sound that becomes the base sound of a syllable, meaning that there is no vowel sound included in its syllable). When compression occurs, the consonant sound blends with the preceding or following syllable instead of creating its own syllable.
In words where syllabic compression exists, it is almost always optional and is based on speaker-preference. Pronunciation dictionaries will show if the compressed form or non-compressed form is more commonly used for each specific word. In the examples below, the commonly preferred number of syllables for each word is bolded and marked with an asterisk /*/.
'Schwa+r' /ɚ/ compression
The uncompressed version of the word is listed first, then the compressed version.
1. difference: /ˈdɪf ɚ əns/, /ˈdɪf rəns/*
2. several: /ˈsɛv ɚ əl/, /ˈsɛv rəl/*
3. temperature: /ˈtɛmp ɚ əʧ ɚ/*, /ˈtɛmp rəʧ ɚ/
'Syllabic l' compression
1. finally: /ˈfɑɪn əl i/*, /ˈfɑɪn li/
2. family: /ˈfæm əl i/, /ˈfæm li/*
3. actually: /ˈæk ʧu əl i/*, /ˈæk ʧu li/
'Syllabic n' compression
1. national: /ˈnæʃ ən əl/*, /ˈnæʃ nəl/
2. additional: /ə ˈdɪʃ ən əl/*, /ə ˈdɪʃ nəl/
Data for more common pronunciation from: Wells, John C. Longman Pronunciation Dictionary. Harlow: Longman, 2007. Print.