olemus
tarkvara, mis töötab ka graafilise kasutajaliideseta, st tummseadmel
=
software capable of working on a device without a graphical user interface

ülevaateid
https://en.wikipedia.org/wiki/Headless_software

https://en.wikipedia.org/wiki/Headless_browser

https://en.wikipedia.org/wiki/Headless_content_management_system