One on bed that might secure a tug? (6)
I believe the answer is:
anchor
'secure a tug?' is the definition.
'anchor' can be an answer for 'secure' (anchoring is a kind of securing). I'm unsure of the 'a tug?' bit.
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for anchor that I've seen before include "Horse-breeding farm" , "Device to keep ship in place" , "Source of stability" , "Ship's mooring at sea" , "Secure (something) firmly in position" .)