The Soil: Texture And Structure
Individual soil particles cluster together to form aggregates.
The term soil structure refers to this aggregation. For example, if you place garden soil on your hand it looks like bread crumbs.
The crumbs are aggregates.
A soil which is well aggregated and includes a range of aggregate sizes is said to be 'well structured'. Conversely, a soil showing little or no aggregation is 'poorly structured'.