Meanings

selection signal

selected area

switched virtual connection

Switched Virtual Circuit

virtual call facility

attribute-value-assertion

coincident-current selection

non-mandatory attribute

optional (O) component

optional user facilities

grade of delivery selection

selection of documents

contextually optional element

contextually optional token

multiple choice (e.g. question)

chooser

answer choices (e.g. for a questionnaire)

selective system

group selection

group selection