Hypothecate

To earmark revenue from a specific tax or levy for a specific, designated purpose, rather than letting it flow into the general exchequer

From Late Latin hypothecare, from Greek hypotheke, 'a pledge or security'

"The reasonable response to the regressivity objection is to hypothecate a share of the HFSS tax's revenue to nutrition programmes serving low-income households, converting a regressive levy into a progressive net transfer."