Calling all bonehead cavers

[Trogger]

Stuck on this cryptic clue from last weekend's crossword:

"Second look pins down bonehead caver" (9).      S---U----.

Am pretty sure the S and U are correct. Any suggestions?  With explanation too please, if not obvious.

 

[andybrooks]

It's gotta be spelunker.  Lousy clue, though.  Bonehead = lunk, and second look = s-peer somehow.

 

[kay]

second = s (abbreviation), very common cryptic crossword device. A rather flabby clue since the "pins down" doesn't have much function except as filling. It certainly doesn't mean "contains" "wraps round" or any other word that would indicate you have to put the "lunk" inside the "peer".

Well done Trogger.

 

[Trogger]

Thanks for that folks, can see why I was struggling! Have heard of spelunker somewhere but never heard of lunk as a 'bonehead'.

 

[Pegasus]

OK Trogger, try this 

http://ukcaving.com/board/index.php?topic=15233.2900

 

[Trogger]

Been unsolved since April I see...
Andys: The letters in your original clue were (11,4) which nobody solved. You didn't give the number of letters in your second clue, the "normal name".