Meaning: A limit or boundary that defines the scope of a particular process or activity.

Part of speech: noun

Example: We need to set clear parameters for the project.

Category: Science › Mathematics

Synonyms:

• criterion
• standard

Meaning: Beyond the range of normal experience or scientific explanation.

Part of speech: adjective

Example: The show explores paranormal phenomena like ghosts.

Category: Science › Supernatural

Meaning: The study of paranormal phenomena, such as telepathy and psychokinesis.

Part of speech: noun

Example: Parapsychology explores the boundaries of human consciousness.

Category: Science › Psychology

Meaning: A very small piece of matter.

Part of speech: noun

Example: Dust particles can be harmful to health.

Category: Science

Synonyms:

• fragment
• speck

Meaning: A device that accelerates charged particles to high speeds.

Part of speech: noun

Example: The particle accelerator is used for research in physics.

Category: Science › Physics

Synonyms: accelerator

Meaning: The branch of physics that studies the properties and interactions of particles.

Part of speech: noun

Example: Particle physics explores the fundamental components of matter.

Category: Science › Physics

Synonyms: high-energy physics

Meaning: Consisting of small particles.

Part of speech: adjective

Example: Particulate matter can affect air quality.

Category: Science

Synonyms: granular

Meaning: A small, rounded mass of material.

Part of speech: noun

Example: The bird ate a pellet of food.

Category: Science

Synonyms:

• grain
• ball

Meaning: Translucently clear; easy to understand.

Part of speech: adjective

Example: The water was pellucid, allowing us to see the fish below.

Category: Science

Synonyms:

• clear
• transparent

Antonyms:

• opaque
• cloudy

Meaning: A weight hung from a fixed point that swings back and forth.

Part of speech: noun

Example: The pendulum of the clock swung steadily.

Category: Science › Physics

Synonyms: swinging weight

Meaning: The partially shaded outer region of a shadow.

Part of speech: noun

Example: The penumbra of the eclipse was visible.

Category: Science › Astronomy

Synonyms:

• shadow
• shade

Meaning: To filter gradually through a porous surface or substance.

Part of speech: verb

Example: The coffee will percolate through the filter.

Category: Science › Chemistry

Synonyms:

• filter
• seep

Meaning: A table that organizes chemical elements based on their properties.

Part of speech: noun

Example: The periodic table is essential for chemistry.

Category: Science › Chemistry

Meaning: An optical instrument for observing from a concealed position.

Part of speech: noun

Example: The submarine used a periscope to see above the water.

Category: Science › Optics

Synonyms:

• viewer
• sight

Meaning: Allowing liquids or gases to pass through.

Part of speech: adjective

Example: The material is permeable to water.

Category: Science › Materials

Synonyms:

• porous
• penetrable

Antonyms:

• impermeable
• sealed

Meaning: To spread throughout something.

Part of speech: verb

Example: The smell of cookies permeated the kitchen.

Category: Science › Chemistry

Synonyms:

• saturate
• infuse

Antonyms:

• contain
• restrict

Meaning: The motion of a machine that, once started, continues indefinitely without any external energy.

Part of speech: noun

Example: Perpetual motion is impossible according to the laws of physics.

Category: Science › Physics

Synonyms: endless motion

Meaning: To spread throughout something.

Part of speech: verb

Example: A sense of calm pervaded the room.

Category: Science › Chemistry

Synonyms:

• spread
• infuse

Meaning: Spreading widely throughout an area or group.

Part of speech: adjective

Example: The pervasive influence of technology is evident in daily life.

Category: Science › Sociology

Synonyms:

• widespread
• ubiquitous

Antonyms: rare

Meaning: A chemical derived from petroleum.

Part of speech: noun

Example: Petrochemicals are used in many everyday products.

Category: Science › Chemistry

Synonyms: chemical

Meaning: A natural liquid found in the earth, used to produce fuel and other products.

Part of speech: noun

Example: Petroleum is a major source of energy.

Category: Science › Geology

Synonyms: oil

Meaning: A scale used to measure acidity or alkalinity of a solution.

Part of speech: noun

Example: The pH of the solution was tested to ensure it was neutral.

Category: Science › Chemistry

Synonyms: acidity scale

Meaning: A distinct period or stage in a process.

Part of speech: noun

Example: We are currently in the planning phase of the project.

Category: Science › General Science

Meaning: Observable events or occurrences.

Part of speech: noun

Example: Natural phenomena like rainbows are fascinating.

Category: Science › General Science

Meaning: An observable event or fact.

Part of speech: noun

Example: The aurora borealis is a natural phenomenon.

Category: Science › General Science

Meaning: A small glass container for holding liquids.

Part of speech: noun

Example: The scientist carefully filled the phial with the solution.

Category: Science › Chemistry

Meaning: A particle of light or electromagnetic radiation.

Part of speech: noun

Example: A photon travels at the speed of light.

Category: Science › Physics

Synonyms: light particle

Meaning: The process by which green plants use sunlight to synthesize foods from carbon dioxide and water.

Part of speech: noun

Example: Photosynthesis is essential for plant growth.

Category: Science › Biology

Synonyms: plant metabolism

Meaning: The study of the shape and size of the skull as a supposed indication of character and mental abilities.

Part of speech: noun

Example: Phrenology was popular in the 19th century but is now considered a pseudoscience.

Category: Science › Psychology

Meaning: Branches of science that study non-living systems, such as physics and chemistry.

Part of speech: noun

Example: Physical science includes subjects like physics and chemistry.

Category: Science › Natural Science

Synonyms: natural science

Meaning: A scientist who studies or practices physics.

Part of speech: noun

Example: The physicist conducted experiments on quantum mechanics.

Category: Science › Physics

Synonyms: scientist

Meaning: The branch of science concerned with the nature and properties of matter and energy.

Part of speech: noun

Example: Physics helps us understand the laws of the universe.

Category: Science › Physics

Synonyms: natural philosophy

Meaning: The branch of biology that deals with the normal functions of living organisms and their parts.

Part of speech: noun

Example: Physiology studies how different systems in the body work together.

Category: Science › Biology

Synonyms: biological science

Meaning: A substance that gives color to materials.

Part of speech: noun

Example: The artist used a bright pigment for the painting.

Category: Science › Chemistry

Synonyms:

• colorant
• dye

Meaning: Containing pigment; colored.

Part of speech: adjective

Example: The pigmented paint gave the wall a vibrant look.

Category: Science › Chemistry

Synonyms:

• colored
• dyed

Antonyms: colorless

Meaning: A very small hole, often used in photography.

Part of speech: noun

Example: The camera uses a pinhole to capture images.

Category: Science › Physics

Synonyms: small hole

Meaning: A unit of liquid capacity equal to 16 fluid ounces.

Part of speech: noun

Example: I ordered a pint of beer.

Category: Science › Measurement

Synonyms: liter

Meaning: Involving new ideas or methods; innovative.

Part of speech: adjective

Example: Her pioneering research changed the industry.

Category: Science › Research

Synonyms: innovative

Meaning: A celestial body orbiting a star, such as Earth.

Part of speech: noun

Example: Mars is the fourth planet from the Sun.

Category: Science › Astronomy

Synonyms:

• world
• celestial body

Meaning: A building or room with a domed ceiling where images of stars and planets are projected.

Part of speech: noun

Example: We visited the planetarium to learn about the universe.

Category: Science › Astronomy

Synonyms: star theater