| SAN | sinoatrial node; sinoauricular node; slept all night; solitary autonomous nodule |
|---|---|
| SPN | senior plan network; sialophorin; solitary pulmonary nodule; supplemental parental nutrition; sympat... |
| SRU | sample ratio units; side rails up; solitary rectal ulcer; structural repeating unit |
| SRUS | solitary rectal ulcer syndrome |
| SURS | solitary ulcer of rectum syndrome; surveillance and utilization review |