Commentary for Psalms 145:16

and satisfy every living thing [with] its desire With a sufficiency to sustain him, He satisfies his goodness, his will, and his blessing. desire Heb. רצון, apayement in Old French, propitiation.

"Open" - and the "you" that's written in the prior verse (Psalm 145:15) is also here, thus [the verse should read] "and You open Your hand," and thus: because the God of my father is my help.

And the meaning of "will" -- what is sufficient for them.