impact

1. 1

   The striking of one body against another; collision.countableuncountable

2. 2

   The force or energy of a collision of two objects.countableuncountable

   • The hatchet cut the wood on impact.
3. 3

   A forced impinging.countableuncountable

   • His spine had an impingement; L4 and L5 made impact, which caused numbness in his leg.
4. 4

   A significant or strong influence or effect.countablefigurativelyproscribed

   • His friend's opinion had an impact on his decision.
   • Our choice of concrete will have a tremendous impact on the building's mechanical performance.

syn. percussion

1. 1

   To collide or strike, the act of impinging.transitive

   • When the hammer impacts the nail, it bends.
2. 2

   To compress; to compact; to press into something or pack together.transitive

   • The footprints of birds do not impact the soil in the way those of dinosaurs do.
3. 3

   To significantly or strongly influence or affect; to have an impact on.figurativelyproscribedtransitive

   • I can make the changes, but it will impact the schedule.
4. 4

   To stamp or impress onto something.raretransitive

   • Ideas impacted on the mind.