1. Submarine: A watercraft capable of independent operation underwater.
  2. Submerge: To put or sink below the surface of water or another liquid.
  3. Subsidize: To support financially; provide a grant or contribution.
  4. Substandard: Below the usual or required standard.
  5. Subdue: To bring under control by force.
  6. Subject: To bring under one’s control or jurisdiction.
  7. Subterranean: Existing, situated, or operating below the surface of the earth.
  8. Suburb: A residential area on the outskirts of a city or large town.
  9. Subsequent: Coming after something in time; following.
  10. Subtle: So delicate or precise as to be difficult to analyze or describe.
  11. Subordinate: Lower in rank or position.
  12. Subscription: A payment or agreement to receive a service or publication regularly.
  13. Subconscious: Of or concerning the part of the mind of which one is not fully aware but which influences one’s actions and feelings.
  14. Substitute: A person or thing acting or serving in place of another.
  15. Subtract: To take away a number or amount from another to calculate the difference.
  16. Subculture: A cultural group within a larger culture, often having beliefs or interests at variance with those of the larger culture.
  17. Subdivision: The act of dividing something into smaller parts.
  18. Subcommittee: A committee composed of some members of a larger committee, board, or other body and reporting to it.
  19. Submission: The action of accepting or yielding to a superior force or to the will or authority of another person.
  20. Subpoena: A writ ordering a person to attend a court.
  21. Substantial: Of considerable importance, size, or worth.
  22. Subatomic: Smaller than or occurring within an atom.
  23. Subjugate: To bring under domination or control, especially by conquest.
  24. Subscription: The action of making or agreeing to make an advance payment in order to receive or participate in something.
  25. Subsonic: Relating to or flying at a speed less than that of sound.
  26. Subscript: A symbol written or printed below the line.
  27. Substation: A set of equipment reducing the high voltage of electrical power transmission to that suitable for supply to consumers.
  28. Subterfuge: Deceit used in order to achieve one’s goal.
  29. Subtitle: Captions displayed at the bottom of a movie or television screen that translate or transcribe the dialogue or narrative.
  30. Subcutaneous: Situated or applied under the skin.
  31. Subversive: Seeking or intended to subvert an established system or institution.
  32. Subdue: Overcome, quieten, or bring under control (a feeling or person).
  33. Subcontinent: A large, distinguishable part of a continent.
  34. Substance: The real physical matter of which a person or thing consists.
  35. Submarine: A vessel that can be submerged and navigated under water.
  36. Submerge: To cause to be under water.
  37. Subcontract: Employ a business or person outside one’s company to do (work) as part of a larger project.
  38. Submerge: Completely cover or obscure.
  39. Suburban: Of or characteristic of a suburb.
  40. Substation: A subsidiary station in which electric current is transformed.
  41. Subterfuge: Deceit used in order to achieve one’s goal.
  42. Subtotal: The total of a part of a group or column of figures.
  43. Subvention: A grant of money, especially from a government.
  44. Subvert: Undermine the power and authority of (an established system or institution).
  45. Suburbia: The suburbs or their inhabitants viewed collectively.
  46. Submersible: Designed to be completely submerged or to operate while submerged.
  47. Subordinate: Treat or regard as of lesser importance than something else.
  48. Subnormal: Below the normal level.
  49. Subscription: An arrangement to receive something, typically a publication, regularly by paying in advance.
  50. Subordination: The action or state of subordinating or of being subordinate.
  51. Subcontinent: A large, distinguishable part of a continent, such as North America or southern Africa.
  52. Subversive: Intending to subvert, especially in an attempt to overthrow or undermine a legally constituted government.
  53. Subfloor: The foundation for a floor in a building.
  54. Subassembly: A unit assembled separately but designed to be incorporated with other units into a larger manufactured product.
  55. Subnuclear: Smaller than the atomic nucleus.
  56. Subtropical: Relating to the regions bordering the tropics.
  57. Subcontractor: A person or company hired by a general contractor to perform a specific task as part of the overall project.
  58. Subclavian: Relating to or denoting an artery or vein that serves the neck and arm on the left and right sides of the body.
  59. Substrate: A substance or layer that underlies something, or on which some process occurs.
  60. Subatomic: Smaller than or occurring within an atom.
  61. Subarctic: Of or relating to the region immediately south of the Arctic Circle.
  62. Submaximal: Less than maximal; not the greatest possible.
  63. Subnational: Relating to or denoting an area or group within a country.
  64. Subfield: A subdivision of a field of study.
  65. Suburbanite: A person who lives in a suburb.
  66. Subgenre: A subdivision of a genre of literature, music, film, etc.
  67. Submersible: A small underwater craft used for deep-sea research.
  68. Subsoil: The soil lying immediately under the surface soil.
  69. Subtherapeutic: Below the dosage levels used to treat diseases.
  70. Subinterval: A smaller interval within a larger interval.
  71. Subcommittee: A committee composed of members of a larger committee, board, or other body.
  72. Subsection: A division of a section.
  73. Subbase: A layer of material in a roadway or airfield pavement system.
  74. Subangular: Having somewhat angular edges.
  75. Subfield: A smaller, specialized field within a broader discipline.
  76. Sublethal: Not quite lethal; insufficient to cause death.
  77. Subdominant: The fourth tone of a diatonic scale.
  78. Subdomain: A domain that is part of a larger domain.
  79. Subprogram: A set of instructions that performs a specific task within a program.
  80. Suboptimal: Below the highest standard or quality.
  81. Subhuman: Below the human level, especially in intelligence or behavior.
  82. Subkingdom: A taxonomic category that ranks below kingdom and above phylum.
  83. Sublinear: Less than linear in relationship.
  84. Submatrix: A matrix formed from a larger matrix by selecting certain rows and columns.
  85. Subglacial: Beneath a glacier or ice sheet.
  86. Sublanguage: A specialized language used by a particular group or in a particular context.
  87. Subpopulation: A distinct group within a larger population.
  88. Subphylum: A taxonomic category that ranks below phylum and above class.
  89. Subfreezing: Below the freezing point.
  90. Subkingdom: A major category in the classification of organisms, ranking below kingdom.
  91. Submucosa: A layer of connective tissue beneath a mucous membrane.
  92. Submersion: The act of submerging or the state of being submerged.
  93. Substratum: An underlying layer or substance, especially a layer of rock or soil beneath the surface of the ground.
  94. Subvocal: Relating to the activity of pronouncing words silently or under one’s breath.
  95. Subcortical: Situated or occurring below the cortex of the brain.
  96. Subemployment: Employment below one’s level of qualification or ability.
  97. Subreption: The act of obtaining something by concealing facts or misrepresenting the truth.
  98. Subinfeudation: The granting of land by a vassal to a sub-vassal.
  99. Subdominant: The fourth note of the diatonic scale, or the chord built on this note.
  100. Subdural: Situated or occurring between the dura mater and the arachnoid membrane of the brain and spinal cord.

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