Those ownedAttributes of a StructuredClassifier that have isComposite = true (see 9.5.3) are called its parts. Hence parts constitute a subset of roles.

Icon class
icon_class
fas fa-quote-left
icon_class_computed
fas fa-quote-left
Related content
SysMLv1: A 'part property' in SysMLv1 does not formally include 'port' (which is considered a special kind of property), even though the Port metaclass in UML2 extends Property and a 'port' may have 'composite' aggregation and be typed by a Block.
Source
Unified Modeling Language 2.5.1
Copyright information
About Object Management Group copyright in text extracts quoted from OMG specifications for educational purposes
Snippet kind
INFO
UML keywords
StructuredClassifier::ownedAttribute
StructuredClassifier
Property::isComposite
AggregationKind::composite
Full quote
Those ownedAttributes of a StructuredClassifier that have isComposite = true (see 9.5.3) are called its parts. Hence parts constitute a subset of roles.
Next snippet
Related snippets
Composite aggregation is a strong form of aggregation that requires a part object be included in at most one composite object at a time. If a composite object is deleted, all of its part instances that are objects are deleted with it.
Aggregation type, navigability, and end ownership are separate concepts, each with their own explicit notation. Association ends owned by classes are always navigable, while those owned by associations may be navigable or not.
A part may be shown by graphical nesting of a box symbol
Related snippets (backlinks)
Visit also
Visit also (backlinks)