impinge v. infringe

Impinge and infringe both mean ‘to intrude on someone’s rights or property’ or ‘to encroach’. Infringe (but not impinge) carries the related meaning ‘to violate an agreement or law’. Impinge (but not infringe) also means ‘to make an impact’ either literally, in the sense of ‘strike’ or ‘collide’, or figuratively, in the sense of ‘having an effect’. So, you can either impinge or infringe on someone’s privacy, but of the two, you can only infringe a patent, and if an idea has an effect on you, it impinges upon your mind.