portStatsPhyIfInDiscards 1.3.6.1.4.1.11.2.3.7.11.33.1.2.1.2.3.1.1.5

The number of inbound packets which were chosen to be discarded even though no errors had been detected to prevent their being deliverable to a higher-layer protocol. One possible reason for discarding such a packet could be to free up buffer space.