An act or process of filling up; a replenishment.(noun)
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Use "fillup" in a sentence
"If most households install solar panels on their roof, with which they "fillup" their own EVs, what will this motley crew going to do for a living?"
"A fillup offaux fur trimming offers a dash of modern, and the practical wool lining will keep your head warm. $40 at Proper Topper 1350 Connecticut Ave. NW, 202-842-3055."
"Tell it to the person who saves a buck on their fillup that it's a gimmick."