Confusion reigns over the acronyms the NFL uses for injuries so here is a quick and dirty explanation.
IR (injured reserve) -player is out for the season (OFS). This frees up a roster spot for another player to join the 53 man roster
PUP (physically Unable to Perform) -player is out at least 6 weeks
IR designated to return -one player per team can have this and it means they can be brought back after 8 weeks.
Now you know. IRvmeans they are done for he season. IR designated to return means they will miss at least 8 weeks