| Abbreviation | Definition |
|---|---|
| FNNG | Florida Naval National Guard |
| FNOC | Fleet Naval Oceanographic Center |
| FNR | Finisher |
| FNR | nisher |
| FNS | Finnish Navy Ship |
| FP1 | pefitter Petty Officer 1st Class |
| FP1 | Pipefitter Petty Officer 1st Class |
| FP2 | pefitter Petty Officer 2nd Class |
| FP2 | Pipefitter Petty Officer 2nd Class |
| FP3 | pefitter Petty Officer 3rd Class |
| FP3 | Pipefitter Petty Officer 3rd Class |
| FPB1 | pefitter (coppersmith) Petty Officer 1st Class |
| FPB1 | Pipefitter (coppersmith) Petty Officer 1st Class |
| FPB2 | pefitter (coppersmith) Petty Officer 2nd Class |
| FPB2 | Pipefitter (coppersmith) Petty Officer 2nd Class |
| FPB3 | pefitter (coppersmith) Petty Officer 3rd Class |
| FPB3 | Pipefitter (coppersmith) Petty Officer 3rd Class |
| FPBC | pefitter (coppersmith) Chief Petty Officer |
| FPBC | Pipefitter (coppersmith) Chief Petty Officer |
| FPBFA | pefitter (coppersmith) Fireman Apprentice |