| Abbreviation | Definition |
|---|---|
| IRB | Inflatable Rescue Boat |
| IWS | In-water Survey |
| IX | Unclassified Miscellaneous (class IX, or 9) |
| IXC | Type IX-C U-Boat |
| JUV | Jack-Up Vessel |
| KDX | Korean Destroyer Experimental |
| KDX-II | Korean Destroyer Experimental, version II |
| LAC | Light Aircraft Carrier |
| LASH | Lighter Aboard SHip |
| LCA | Landing Craft Assault |
| LCC | Landing Craft Command |
| LCF | Landing Craft, Fire support |
| LCG | Landing Craft Gunboat |
| LCH | Landing Craft Hospital |
| LCI(G) | Landing Craft Infantry (Gunboat) |
| LCL | Landing Craft Large |
| LCL | Landing Craft Logistics |
| LCP | Landing Craft Personnel |
| LCP(R) | Landing Craft Personnel, Ramp |
| LCR | Landing Craft Ramp |