emblem on banner
綮 centers on a symbolic emblem or insignia displayed on a banner, representing a mark of identity or authority.
綮 combines 糸 (thread, cloth) with a phonetic element that includes 戸 and 攵, likely representing a sound like ケイ. The character originally referred to an embroidered emblem on a banner.
Picture a banner with the 糸 (thread) component at the bottom, as if the emblem is woven into the fabric. The upper part looks like a door (戸) with a striking action (攵), like a herald announcing the emblem.
For ケイ, imagine a banner with a large letter 'K' (ケイ) embroidered on it, standing for the kingdom's emblem.