losing my mind about sytnax error in window clause

Hi Folks,

I've been reading the docs over and again, searching exhaustively for
examples on the internet to help me here and I'm ready to give up.

I have a query using windows function:

SELECT
last_value ( typechange ) OVER w,
pindex,
lid,
last_value ( modified ) OVER w,
last_value ( created ) OVER w,
last_value ( modifiedby ) OVER w,
last_value ( createby ) OVER w,
last_value ( cost ) FILTER ( WHERE cost IS NOT NULL ) OVER w,
last_value ( sell ) FILTER ( WHERE sell IS NOT NULL ) OVER w
FROM ps._delta_ext
WHERE pindex = Ppindex AND
( Plid IS NULL OR lid = Plid ) AND
( Ptimestamp IS NULL OR modified <= Ptimestamp )
GROUP BY lid, pindex
WINDOW w AS ( PARITION BY lid, pindex ORDER BY created );
Complains about syntax error in the WINDOW cause (last line) on [PARTITION]
BY:
/* messages
ERROR: syntax error at or near "BY"
LINE 16: WINDOW w AS ( PARITION BY locationid, partindex ORDER BY cr...
^
SQL state: 42601
Character: 2724
*/

Maybe my error is clear to someone else, could really use helping hand,
thanks.

Rein