Plural: impacts → impingements, encroachments, shocks, impressions…
Past participle: impacted
e.g. impacted → affected, touched, stroked, contacted…

Choose the right word

Impact, Concussion or Collision?

Concussion is often by transmitted force rather than by direct impact; two railway-trains come into collision; an explosion of dynamite shatters neighboring windows by concussion. Impact is the blow given by the striking body; as, the impact of the cannon-shot upon the target.

J. C. Fernald, English Synonyms and Antonyms (1914)

Example sentences

hit Even after it was hit, the pole was still upright.
affect Petrol prices affect us all in one way or another.

Popularity over time

Word	1850 → 2019	Trend
impact		rising
hit		rising
affect		steady

Use in printed books, per decade from 1850 to 2019.

By length

3 letters: hit¹
4 letters: cram¹
5 letters: force¹, touch¹, shock¹, pound¹
6 letters: affect², stroke¹, wallop²
7 letters: contact², impinge²
8 letters: striking²
9 letters: collision³
10 letters: impression³, concussion³, percussion³
11 letters: impingement
12 letters: encroachment³

The small number after each word is its number of syllables (affect² = 2 syllables).