main stress

It is also referred to as primary stress. If a word has more than one syllable (is 'multisyllabic'), one syllable will be more strongly stressed than the others. That syllable is the main stress. There are three levels of word stress in English: primary, secondary and tertiary. Most multisyllabic words have only primary and tertiary stress. If you find it difficult to identify the primary stress, it may be because there is a secondary stress (e.g, interesting, narrow). In transcription the primary stress is indicated by a straight apostrophe-like symbol before the primary stressed syllable, while the secondary stress (if shown) is indicated by a straight comma-like symbol before the secondary stressed syllable.

e.g. interesting  / ˈɪnˌtrəstɪŋ/

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