anchor
矴 centers on a heavy object used to hold a vessel in place: an anchor. The single given meaning is concrete and specific.
矴 combines 石 (stone) with 丁, which likely contributes the sound. The character suggests a stone used as an anchor.
A stone 石 shaped like a hook 丁: picture a heavy stone anchor with a T-shaped top, dropped into the sea to hold a boat steady.
For テイ, imagine a heavy stone anchor being lowered from a table: table -> テイ, and the anchor holds the ship in place.