Definition:

Syllable Structure

Based on the number of Syllables in a word, they can be divided into monosyllabic, disyllabic, and trisyllabic words, etc. 

Word Stress

A very important feature of spoken English. If a word has more than one syllable, all the syllables are not equally Prominent, one of the syllables is more prominent than the others. That syllable is said to receive stress.