Metrical phonology is a phonological theory concerned with organizing segments into groups of relative prominence. Segments are organized into syllables, syllables into metrical feet, feet into phonological words, and words into larger units.
This organization is represented formally by metrical trees and grids.
Here is an example of a metrical tree of the word metricality:
On the word and foot level, s and w indicate relative stress. The w indicates weaker prominence, and the s indicates relative stronger prominence.
The internal syllable structure in the above figure has been omitted and is represented by triangles. Within the syllable, s and w refer to stronger and weaker degrees of sonorance, not stress, and s corresponds to the syllable nucleus, which is the most sonorant segment in a syllable.
In metrical trees, the strongest unit of the word is the one that is dominated by s all the way up the tree.
Here is an example of a metrical grid of the word metricality:
Stress within feet and words can be represented as a metrical grid:
In a grid, the most prominent unit is the one that is dominated by the most number of x’s.