13-letter words containing s, p, o, i
- spelling book — an elementary textbook or manual to teach spelling
- spelling-book — a person who spells words.
- spermatogenic — relating to the development of spermatozoa
- spermatotoxic — spermotoxic.
- spermatotoxin — spermotoxin.
- sphagnicolous — growing in moss
- sphagnologist — a person who studies sphagna
- sphenoid bone — the large butterfly-shaped compound bone at the base of the skull, containing a protective depression for the pituitary gland
- spheristerion — an area designated for ballplay
- spherocytosis — the condition of having spherocytes
- spheroidicity — a spheroidal state or form.
- sphingomyelin — any of the class of phospholipids occurring chiefly in the brain and spinal cord, composed of phosphoric acid, choline, sphingosine, and a fatty acid.
- spider flower — cleome
- spider monkey — any of several tropical American monkeys of the genus Ateles, having a slender body, long, slender limbs, and a long, prehensile tail: some are endangered.
- spider orchid — any of several European orchids of the genus Ophrys, esp O. sphegodes, having a flower with yellow, green, or pink sepals and a broad brown velvety lip
- spinal column — the series of vertebrae in a vertebrate animal forming the axis of the skeleton and protecting the spinal cord; spine; backbone.
- spinuliferous — relating to a spine or spines
- spiny dogfish — any of several dogfish sharks of the genus Squalus, having a spine in front of each of the two dorsal fins, especially S. acanthias, inhabiting Atlantic coastal waters.
- spiny lobster — any of several edible crustaceans of the family Palinuridae, differing from the true lobsters in having a spiny shell and lacking the large pincers.
- spiritousness — the state of being spiritous
- spirochetosis — a disease caused by infection with a spirochete.
- splendiferous — splendid; magnificent; fine.
- splenectomize — to remove the spleen from
- splenial bone — a small bone in the lower jaw of some animals, such as reptiles and birds
- spoiler party — a third political party formed to draw votes away from one of the two major parties, thus spoiling its chance of winning an election.
- spoils system — the system or practice in which public offices with their emoluments and advantages are at the disposal of the victorious party for its own purposes.
- spokesmanship — the office or skilful use of the office of spokesman
- spondylolysis — the destruction of the vertebra
- sponge finger — sweet finger-shaped biscuit
- spontaneities — the exhibiting of actions, impulses, or behaviour that are stimulated by internal processes
- sporopollenin — an inert, tough polymer forming the resistant outer coat of a pollen grain or spore.
- sporting lady — a prostitute.
- sports injury — wound sustained while playing sport
- sports writer — A sports writer is a journalist who writes about sport.
- sportscasting — the reporting of a sports event by radio or television broadcast.
- sportsmanlike — a man who engages in sports, especially in some open-air sport, as hunting, fishing, racing, etc.
- sportsmanship — the character, practice, or skill of a sportsman.
- sportswriting — the work of a sports writer
- spot lighting — Spot lighting is lighting directed towards and used to draw attention to a product or display.
- spot reducing — the usually futile effort to exercise one part of the body, as the thighs, in hopes of reducing the amount of fat stored in that area.
- spread option — spread (def 25b).
- spring-loaded — (of a machine part) kept normally in a certain position by a spring: a spring-loaded safety valve.
- springboarded — a flexible board, projecting over water, from which divers leap or spring.
- spurious wing — alula (def 1).
- standing chop — (in an axemen's competition) a chop with the log standing upright
- standing crop — the totality of living things in an ecosystem at a given time.
- starting post — the upright pole marking the beginning of a racecourse
- state capitol — the building which houses the government of a state
- staying power — ability or strength to last or endure; endurance; stamina.
- step aerobics — a set of aerobic exercises designed to improve the cardiovascular system, which consists of stepping on and off a special box of adjustable height