Pack animal carrying Tibetan leader (4)
I believe the answer is:
stow
'pack' is the definition.
(I know that stow is a type of pack)
'animal carrying tibetan leader' is the wordplay.
'animal' becomes 'sow' (female pig).
'carrying' is an insertion indicator.
'leader' suggests taking the first letters.
The initial letter of 'tibetan' is 't'.
'sow' going around 't' is 'STOW'.
(Other definitions for stow that I've seen before include "Pack tightly" , "- - -on-the-Wold" , "Lay up, pack away" , "Pack, put away" , "Pack or store carefully, luggage perhaps" .)