definition of
boil down

[1] #1 boil down v. be the essential element; "The proposal boils down to a compromise". wn

[2] #2 boil down v. be cooked until very little liquid is left; "The sauce should reduce to one cup". wn

[3] #3 boil down v. cook until very little liquid is left; "The cook reduced the sauce by boiling it for a long time". wn