The term “Directioned” in WDM systems means that the wavelength carrying local services can be transmitted in a specific direction. This contrasts with directionless systems, where wavelengths can propagate in either direction without restriction. Directioned capability allows more controlled and secure wavelength routing, especially in ring or mesh networks where traffic flows need clear paths. Colorless refers to wavelength independence (a device can handle any wavelength), while colored means the device or port is assigned to a fixed wavelength. Thus, directioned accurately describes the wavelength propagation direction property as per HCIP-Transmission explanations on optical network design and wavelength routing.