But wait:

Impact is also a verb!

Webster 1913 is a touch old; I think language has evolved a bit in 88 years. You should know that impact isn't the only verbed noun.

Other nouns that have been verbed in the past century include:

Steven Pinker in The Language Instinct proposes that a great number English verbs were once nouns. "It is one of the processes that make English English," he says.
I have estimated that about a fifth of all English verbs were once nouns. Considering just the human body, you can head a committee, scalp the missionary, eye a babe, nose around the office, mouth the lyrics, gum the biscuit, begin teething, tongue each note on the flute, jaw at the referee, neck in the back seat, back a candidate, arm the militia, shoulder the burden, elbow your way in, hand him a toy, finger the culprit, knuckle under, thumb a ride, wrist it into the net, belly up to the bar, stomach someone's complaints, rib you drinking buddies, knee the goalie, leg it across town, heel on command, foot the bill, toe he line, and several others that I cannot print in a family language book
So, it's fine to use impact as a verb.

Source: The Language Instinct by Steven Pinker.