The most common and most likely answer to this crossword clue is the 4 plus 4 letter word REEF KNOT
I've seen this crossword clue in The Daily Telegraph
R
E
E
F
K
N
O
T
More clues leading to the result REEF KNOT
- It secures two terms at sea
- Does it make the bank secure?
- No granny may be free to kiss Nick or Tom’s heads
- Bank on bird’s entanglement
- Might this tie one up on rocks at sea?
- Reduce speed of maritime connection
- Bond bird hit fellow getting uppity?
- Something to secure sails oftener crumpled across end of deck
- What could secure two birds separated by one foot
- How to tie up on rocks at sea?
Buddy explains!

The straight part
We know that "Sailor’s hand-made joint" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sailor’s hand-made joint = reef knot.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.