| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Oak Acres | city | Maryland | United States | 39.41 | -77.32 | 830 | |
| Oak Court | city | Maryland | United States | 38.98 | -76.55 | 49 | |
| Oak Crest | city | Maryland | United States | 39.09 | -76.86 | 180 | |
| Oak Dale | city | Maryland | United States | 39.55 | -76.29 | 393 | |
| Oak Estates | city | Maryland | United States | 38.50 | -76.78 | 147 | |
| Oak Forest | city | Maryland | United States | 39.26 | -76.74 | 400 | |
| Oak Forest Park | city | Maryland | United States | 39.26 | -76.75 | 400 | |
| Oak Grove | city | Maryland | United States | 39.71 | -76.08 | 344 | |
| Oak Grove | city | Maryland | United States | 38.87 | -76.78 | 101 | |
| Oak Grove | city | Maryland | United States | 39.07 | -76.53 | 22 | |
| Oak Haven | city | Maryland | United States | 38.43 | -75.57 | 36 | |
| Oak Hill | city | Maryland | United States | 39.39 | -76.63 | 400 | |
| Oak Hill Estates | city | Maryland | United States | 38.21 | -75.29 | 16 | |
| Oak Hill Estates | city | Maryland | United States | 38.59 | -76.99 | 157 | |
| Oak Hill Estates | city | Maryland | United States | 39.13 | -76.97 | 830 | |
| Oak Hollow | city | Maryland | United States | 39.11 | -76.55 | 49 | |
| Oak Knolls | city | Maryland | United States | 38.58 | -76.99 | 160 | |
| Oak Landing | city | Maryland | United States | 39.08 | -76.53 | 3 | |
| Oak Lea | city | Maryland | United States | 39.28 | -76.86 | 347 | |
| Oak Orchard | city | Maryland | United States | 39.49 | -77.15 | 830 | |
| Oak Park | city | Maryland | United States | 39.24 | -76.68 | 49 | |
| Oak Park | city | Maryland | United States | 39.48 | -77.59 | 830 | |
| Oak Ridge | city | Maryland | United States | 39.55 | -76.34 | 272 | |
| Oak Ridge | city | Maryland | United States | 39.19 | -77.31 | 347 | |
| Oak Ridge | city | Maryland | United States | 39.62 | -77.75 | 830 | |
| Oak Ridge Manor | city | Maryland | United States | 39.15 | -76.62 | 49 | |
| Oak Springs | city | Maryland | United States | 39.08 | -76.98 | 321 | |
| Oak Summit | city | Maryland | United States | 39.39 | -76.51 | 291 | |
| Oak Terrace Trailer Park | city | Maryland | United States | 38.47 | -75.76 | 19 | |
| Oak Valley | city | Maryland | United States | 39.66 | -76.59 | 830 | |
| Oak View Village | city | Maryland | United States | 39.17 | -76.83 | 347 | |
| Oak West | city | Maryland | United States | 39.28 | -76.81 | 347 | |
| Oakbluff | city | Maryland | United States | 38.94 | -76.54 | 3 | |
| Oakdale | city | Maryland | United States | 39.13 | -77.07 | 830 | |
| Oakdale | city | Maryland | United States | 39.34 | -76.41 | 3 | |
| Oakdale | city | Maryland | United States | 39.11 | -76.64 | 95 | |
| Oakdale Acres | city | Maryland | United States | 38.43 | -75.57 | 32 | |
| Oakdale Manor | city | Maryland | United States | 39.59 | -76.86 | 830 | |
| Oakhill | city | Maryland | United States | 39.09 | -76.57 | 49 | |
| Oakhurst | city | Maryland | United States | 39.42 | -76.49 | 308 | |
| Oakhurst | city | Maryland | United States | 39.10 | -76.94 | 830 | |
| Oakington | city | Maryland | United States | 39.50 | -76.11 | 0 | |
| Oakington Manor | city | Maryland | United States | 39.51 | -76.13 | 3 | |
| Oakland | city | Maryland | United States | 39.41 | -79.41 | 2509 | |
| Oakland | city | Maryland | United States | 38.81 | -76.54 | 3 | |
| Oakland | city | Maryland | United States | 39.71 | -76.69 | 830 | |
| Oakland | city | Maryland | United States | 38.99 | -75.88 | 55 | |
| Oakland | city | Maryland | United States | 39.42 | -76.88 | 830 | |
| Oakland | city | Maryland | United States | 38.86 | -76.91 | 249 | |
| Oakland Acres | city | Maryland | United States | 38.98 | -75.86 | 59 | |
| Oakland Acres | city | Maryland | United States | 38.31 | -75.56 | 42 | |
| Oakland Acres | city | Maryland | United States | 38.50 | -76.78 | 147 | |
| Oakland Estates | city | Maryland | United States | 38.52 | -76.97 | 108 | |
| Oakland Hill | city | Maryland | United States | 39.05 | -76.47 | 6 | |
| Oakland Hills | city | Maryland | United States | 39.41 | -76.90 | 830 | |
| Oakland Mills | city | Maryland | United States | 39.22 | -76.84 | 400 | |
| Oakland Park | city | Maryland | United States | 39.37 | -76.77 | 830 | |
| Oaklands | city | Maryland | United States | 38.74 | -76.10 | 3 | |
| Oaklawn | city | Maryland | United States | 38.77 | -76.95 | 203 | |
| Oaklee Village | city | Maryland | United States | 39.27 | -76.68 | 154 | |
| Oakleigh | city | Maryland | United States | 39.41 | -76.56 | 830 | |
| Oakleigh Forest | city | Maryland | United States | 39.08 | -76.54 | 3 | |
| Oakleigh Manor | city | Maryland | United States | 39.40 | -76.56 | 351 | |
| Oakleigh Ridge | city | Maryland | United States | 39.70 | -76.93 | 928 | |
| Oaklett Estates | city | Maryland | United States | 39.69 | -77.82 | 416 | |
| Oakley | city | Maryland | United States | 38.27 | -76.74 | 3 | |
| Oaklyn Manor | city | Maryland | United States | 39.43 | -76.38 | 95 | |
| Oakmont | city | Maryland | United States | 39.00 | -77.11 | 347 | |
| Oakmont | city | Maryland | United States | 39.54 | -76.43 | 416 | |
| Oakmont | city | Maryland | United States | 39.04 | -76.48 | 49 | |
| Oakmont Manor | city | Maryland | United States | 39.13 | -77.18 | 830 | |
| Oakridge | city | Maryland | United States | 39.66 | -75.81 | 114 | |
| Oakridge | city | Maryland | United States | 39.33 | -77.32 | 400 | |
| Oakridge Mobile Home Park | city | Maryland | United States | 38.33 | -75.69 | 19 | |
| Oaks | city | Maryland | United States | 38.50 | -76.78 | 147 | |
| Oaks of Harford | city | Maryland | United States | 39.47 | -76.32 | 82 | |
| Oaks of Parsonage | city | Maryland | United States | 39.65 | -76.71 | 830 | |
| Oaks of Severna Park | city | Maryland | United States | 39.09 | -76.57 | 49 | |
| Oakview | city | Maryland | United States | 39.02 | -76.98 | 259 | |
| Oakville | city | Maryland | United States | 38.22 | -75.62 | 32 | |
| Oakville | city | Maryland | United States | 38.39 | -76.64 | 98 | |
| Oakwood | city | Maryland | United States | 39.70 | -76.18 | 305 | |
| Oakwood | city | Maryland | United States | 38.92 | -76.47 | 3 | |
| Oakwood | city | Maryland | United States | 38.57 | -77.03 | 154 | |
| Oakwood | city | Maryland | United States | 38.62 | -76.96 | 200 | |
| Oakwood | city | Maryland | United States | 39.54 | -76.22 | 351 | |
| Oakwood Knolls | city | Maryland | United States | 38.99 | -77.13 | 298 | |
| Oakwood Manor | city | Maryland | United States | 39.15 | -76.62 | 49 | |
| Oakwood Overlook | city | Maryland | United States | 39.25 | -76.98 | 830 | |
| Oakwood Park | city | Maryland | United States | 39.14 | -76.61 | 49 | |
| Oakwood Village | city | Maryland | United States | 39.36 | -76.79 | 830 |