subway noun An underground railway system used for public transportation in a city. She takes the subway to work every morning to avoid traffic. + submarine noun A watercraft capable of operating underwater, used for military, scientific, or exploration purposes. The submarine descended slowly to study creatures living near the ocean floor. + subtract verb To take one number or amount away from another in order to find the difference. If you subtract fifteen from fifty, you are left with thirty-five. + subheading noun A heading given to a section within a larger piece of writing, placed below the main title. Each chapter used clear subheadings to help readers navigate the different topics. + submerge verb To put or go completely under the surface of water or another liquid. The divers submerged themselves to explore the sunken ship near the reef. + subordinate noun A person who works under the authority or direction of someone of higher rank. The manager praised her subordinates for meeting the tight deadline. + subscribe verb To arrange to regularly receive or pay for a publication, service, or product. She subscribed to a monthly magazine about gardening and home design. + subside verb To become gradually less intense, or to sink to a lower level. The pain in her ankle finally began to subside after a week. + subsidy noun Money given by a government or organization to support an industry, activity, or price. The government offers a subsidy to farmers who grow organic crops. + substitute noun A person or thing that takes the place of another, especially when the original is unavailable. The coach sent in a substitute after the star player twisted his ankle. + suburb noun A residential district located on the outskirts of a city or large town. They moved to a quiet suburb to have more space for their growing family. + subtotal noun The sum of a set of numbers within a larger calculation, not including tax, discounts, or later additions. The receipt listed a subtotal of forty dollars before sales tax was added. + subtle adjective So delicate or precise as to be difficult to detect or describe; not obvious. There was a subtle change in her tone that suggested she wasn't telling the whole story. + subtitle noun Text shown on a screen that translates or transcribes the spoken dialogue of a film or video. We turned on the English subtitle because the actors spoke very quickly. + subvert verb To undermine or weaken the power, authority, or stability of an established system. The propaganda campaign aimed to subvert public trust in the election results. + subset noun A smaller group or part of a larger set, whose members all belong to that larger set. Only a small subset of the survey respondents had ever traveled abroad. + subsoil noun The layer of soil lying just beneath the surface topsoil, usually less fertile and containing more clay or minerals. The gardener dug past the dark topsoil into the pale, compacted subsoil below. + subplot noun A secondary storyline that runs alongside the main plot of a book, play, or film. The novel's subplot about the missing letter added extra suspense. + subgroup noun A smaller group formed by dividing a larger group according to a shared characteristic. Researchers analyzed a subgroup of patients over the age of sixty. + subzero adjective Describing a temperature that falls below zero degrees on a given scale. Subzero temperatures froze the lake solid within a single week. + subpar adjective Below an expected, average, or acceptable standard of quality or performance. The restaurant closed early after receiving several complaints about subpar service. + submit verb To present something, such as a document or proposal, for consideration or approval. Students must submit their final essays by Friday afternoon this week. + subsequent adjective Coming after something else in time or order. The initial trial succeeded, and subsequent tests confirmed the results. + substandard adjective Below the usual or acceptable quality or standard. The inspector condemned the building because of substandard wiring throughout. + subconscious adjective Relating to mental processes that occur without a person's full awareness. Her subconscious fear of failure kept her from applying for the job. + subcontract verb To hire another person or company to perform part of a job one has already agreed to complete. The main contractor subcontracted the plumbing work to a smaller firm. + subdivide verb To divide something that has already been divided into smaller parts. The developer plans to subdivide the farmland into residential lots. + subdue verb To overcome, defeat, or bring under control, often through force or great effort. The firefighters worked for hours to subdue the blaze before it reached nearby houses. + sublease verb To rent out property that one is already renting from someone else. She decided to sublease her apartment while studying abroad for a semester. + subsist verb To survive with only the most basic necessities, especially food. The remote mountain village subsisted mainly on fish and wild rice. +