| 1. hydrant |  | 53. hydrodynamics |
| 2. hydraulic | | 54. hydrofoil |
| 3. hydraulic accumulator | | 55. hydrofoil bilge keel |
| 4. hydraulic beaches | | 56. hydrofoil boat |
| 5. hydraulic circuit | | 57. hydrofoil craft |
| 6. hydraulic clutch | | 58. hydrofoil ship |
| 7. hydraulic coupling | | 59. Hydrofoil Small Waterplane Area Ship (HYSWAS) |
| 8. hydraulic cylinder | | 60. hydrofoil with inherent stability |
| 9. hydraulic derrick | | 61. hydrofoil with partly submerged foils |
| 10. hydraulic dredger | | 62. hydrofoil with surface piercing foils |
| 11. hydraulic drive | | 63. hydrogen |
| 12. hydraulic fluid | | 64. hydroglider |
| 13. hydraulic jack | | 65. hydrograph |
| 14. hydraulic jet propulsion | | 66. hydrographer |
| 15. hydraulic log | | 67. hydrographic office |
| 16. hydraulic pressure | | 68. hydrographic service |
| 17. hydraulic propulsion | | 69. hydrographic ship |
| 18. hydraulic riveter | | 70. hydrographic survey |
| 19. hydraulic solenoid valve | | 71. Hydrographic survey equipment of RMN's survey vessel PERANTAU |
| 20. hydraulic starting | | 72. Hydrographic survey systems of Royal Australian Navy's survey vessel LEUWIN |
| 21. hydraulic steering gear | | 73. Hydrographic survey vessel |
| 22. hydraulic suction dredger | | 74. hydrographic surveyor |
| 23. hydraulic test | | 75. hydrographical publications |
| 24. hydraulic torque converter | | 76. hydrography |
| 25. hydraulic trigger | | 77. hydroid |
| 26. hydraulic wake | | 78. hydrokeel |
| 27. hydro-dump | | 79. hydrolant |
| 28. hydro-engineering | | 80. hydrolic |
| 29. hydro-ski | | 81. Hydrologic cycle |
| 30. hydro-ski vehicle | | 82. hydrology |
| 31. hydroacoustic buoy | | 83. hydromechanics |
| 32. hydroacoustic noise | | 84. hydrometeors |
| 33. hydroacoustic ship | | 85. hydrometer |
| 34. hydroacoustics | | 86. hydropac |
| 35. Hydroblasting | | 87. hydrophone |
| 36. hydrocarbon | | 88. hydrophore |
| 37. Hydrocarbon gas | | 89. hydroplane |
| 38. hydrochloric acid | | 90. hydroplane float |
| 39. hydrocrackate | | 91. Hydropnuematic testing |
| 40. hydrocracker | | 92. hydroskimmer |
| 41. hydrodealkylation (HDA) | | 93. hydrosphere |
| 42. hydrodynamic | | 94. hydrostatic curves |
| 43. hydrodynamic angle of attack of blade element | | 95. hydrostatic diaphragm |
| 44. hydrodynamic characteristic | | 96. hydrostatic lift |
| 45. hydrodynamic characteristics of the rudder | | 97. hydrostatic release |
| 46. hydrodynamic force | | 98. Hydrostatic release unit |
| 47. hydrodynamic impact | | 99. hydrostatic test |
| 48. hydrodynamic pitch | | 100. hydrostatics |
| 49. hydrodynamic pressure | | 101. hydrotechnics |
| 50. hydrodynamical pitch | | 102. Hydrotrac gear unit |
| 51. hydrodynamical pitch angle | | 103. hydrotreating |
| 52. hydrodynamically unbalanced screw | |
