To fill is defined as to put as much as possible or to occupy.(verb)
An example of to fill is putting as much salt into a salt shaker as will fit.
The definition of fill is to supply what is needed, satisfy, close or put a person into.(verb)
See fill in Webster's New World College Dictionary
Origin: ME fillen, fullen < OE fyllan < Gmc *fulljan, to make full < *fulla- (> Goth fulls, full) + -jan, caus. suffix
See fill in American Heritage Dictionary 4
verb filled, fill·ing, fills verb, transitive
Origin: Middle English fillen
Origin: , from Old English fyllan; see pelə-1 in Indo-European roots.
Learn more about fill