Ship from Latvia being loaded up (6)
I believe the answer is:
vessel
'ship' is the definition.
(I know that ship can be written as vessel)
'latvia being loaded up' is the wordplay.
'latvia' becomes 'lv' (I can't explain this - if you can you should believe this answer much more).
'being' becomes 'esse' (I've seen this in other clues).
'loaded' indicates putting letters inside.
'up' is a reversal indicator (in down clue: letters go upwards).
'lv' going around 'esse' is 'lessev'.
'lessev' back-to-front is 'VESSEL'.
'from' is the link.
Can you help me to learn more?
(Other definitions for vessel that I've seen before include "bowl?" , "A ship, a cup" , "Bark, possibly, needing water" , "Container for liquid or craft for water" , "Ship, or artery" .)