A bunch of crims assume a yoga position as a way to get on board (9)
I believe the answer is:
gangplank
'a way to get on board' is the definition.
(I've seen this before)
'a bunch of crims assume a yoga position' is the wordplay.
I cannot really understand how this works, but
'a' could be 'an' and 'an' is present in the answer.
This explanation may well be incorrect...
'as' is the link.
Can you help me to learn more?
(Other definitions for gangplank that I've seen before include "crew has put down roughly" , "Bridge for walking onto ship" , "way of leaving Britannia?" , "Board boat here" , "way to get on board" .)