Meaning: not carrying a load or burden.

Part of speech: adjective

Example: The unladen ship sailed smoothly across the sea.

Category: Science

Synonyms:

• empty
• light

Antonyms:

• laden
• loaded

Meaning: Not demonstrated to be true or valid.

Part of speech: adjective

Example: The theory remains unproven.

Category: Science › Research

Synonyms:

• unverified
• untested

Antonyms:

• proven
• verified

Meaning: Not documented or officially noted.

Part of speech: adjective

Example: Many unrecorded species exist in the rainforest.

Category: Science › Biology

Synonyms:

• unnoted
• unregistered

Antonyms:

• recorded
• documented

Meaning: Not processed or purified; crude.

Part of speech: adjective

Example: The oil was unrefined and had a strong taste.

Category: Science › Chemistry

Synonyms:

• crude
• raw

Antonyms:

• refined
• processed

Meaning: Not connected or associated with something.

Part of speech: adjective

Example: The two events were unrelated.

Category: Science › Biology

Synonyms:

• independent
• disconnected

Antonyms:

• related
• connected

Meaning: not based on or consistent with scientific methods

Part of speech: adjective

Example: His claims were dismissed as unscientific.

Category: Science

Synonyms:

• irrational
• unfounded

Antonyms:

• scientific
• empirical

Meaning: not resolved or figured out

Part of speech: adjective

Example: The mystery remains unsolved after many years.

Category: Science

Synonyms:

• unresolved
• inconclusive

Antonyms:

• solved
• resolved

Meaning: not backed by evidence or support

Part of speech: adjective

Example: The theory was unsupported by any research.

Category: Science

Synonyms:

• unproven
• unsubstantiated

Antonyms:

• supported
• proven

Meaning: Not tested or proven.

Part of speech: adjective

Example: The untried method showed promise in early experiments.

Category: Science

Synonyms:

• unproven
• untested

Antonyms:

• tried
• tested

Meaning: A radioactive element used as fuel in nuclear reactors.

Part of speech: noun

Example: Uranium is essential for nuclear energy.

Category: Science › Chemistry

Synonyms:

• element
• fuel

Meaning: The seventh planet from the Sun in our solar system.

Part of speech: noun

Example: Uranus is known for its unique tilt.

Category: Science › Astronomy

Synonyms: planet

Meaning: A constellation in the northern sky.

Part of speech: noun

Example: Ursa Major contains the Big Dipper.

Category: Science › Astronomy

Synonyms: Great Bear

Meaning: A constellation in the northern sky, smaller than Ursa Major.

Part of speech: noun

Example: Ursa Minor is home to the North Star.

Category: Science › Astronomy

Synonyms: Little Bear

Meaning: Ultraviolet light, a type of electromagnetic radiation.

Part of speech: noun

Example: UV rays can cause skin damage.

Category: Science › Physics

Synonyms: ultraviolet radiation

Meaning: Ultraviolet A rays, a type of UV radiation.

Part of speech: noun

Example: UVA rays penetrate the skin more deeply.

Category: Science › Physics

Meaning: Ultraviolet B rays, a type of UV radiation responsible for sunburn.

Part of speech: noun

Example: UVB rays are strongest during midday.

Category: Science › Physics

Meaning: Ultraviolet C rays, a type of UV radiation that is mostly absorbed by the atmosphere.

Part of speech: noun

Example: UVC rays are not a concern for skin health.

Category: Science › Physics

Meaning: a space within a cell that contains fluid

Part of speech: noun

Example: The plant cell has a large vacuole.

Category: Science › Biology

Meaning: a space entirely devoid of matter

Part of speech: noun

Example: In space, there is a vacuum.

Category: Science › Physics

Synonyms:

• void
• emptiness

Meaning: the combining capacity of an element

Part of speech: noun

Example: Oxygen has a valency of two.

Category: Science › Chemistry

Synonyms: valence

Meaning: to confirm or support the truth of something

Part of speech: verb

Example: You need to validate your findings with evidence.

Category: Science

Synonyms:

• confirm
• authenticate

Meaning: not influenced by personal beliefs or opinions

Part of speech: adjective

Example: The research aims to be value-free.

Category: Science › Research

Synonyms:

• objective
• neutral

Meaning: a chemical element used in steel production

Part of speech: noun

Example: Vanadium is important for making strong steel.

Category: Science › Chemistry

Meaning: A device that shows the direction of the wind.

Part of speech: noun

Example: The weather vane on the roof spins in the breeze.

Category: Science › Meteorology

Synonyms:

• wind indicator
• weather vane

Meaning: A compound that gives vanilla its flavor and aroma.

Part of speech: noun

Example: Vanillin is often used in perfumes and food.

Category: Science › Chemistry

Synonyms:

• flavoring
• aroma compound

Meaning: A substance in the gas phase.

Part of speech: noun

Example: Water vapor rises into the air when it boils.

Category: Science › Physics

Synonyms:

• gas
• mist

Antonyms:

• liquid
• solid

Meaning: A visible trail of condensed water vapor left by an aircraft.

Part of speech: noun

Example: The vapor trail of the jet was visible against the blue sky.

Category: Science › Aviation

Synonyms:

• contrail
• cloud trail

Meaning: To convert a substance into vapor.

Part of speech: verb

Example: The heat will vaporize the liquid quickly.

Category: Science › Physics

Synonyms:

• evaporate
• steam

Antonyms:

• condense
• solidify

Meaning: Consisting of vapor; misty.

Part of speech: adjective

Example: The vaporous clouds floated in the sky.

Category: Science › Physics

Synonyms:

• misty
• hazy

Antonyms:

• clear
• solid

Meaning: The quality of being subject to change.

Part of speech: noun

Example: The variability in temperature can affect plant growth.

Category: Science › Statistics

Synonyms:

• changeability
• fluctuation

Antonyms:

• stability
• consistency

Meaning: A factor that can change in an experiment.

Part of speech: noun

Example: In the experiment, temperature is the variable we will measure.

Category: Science › Mathematics

Synonyms:

• factor
• element

Meaning: The difference between values in a set.

Part of speech: noun

Example: The variance in scores showed how much students differed.

Category: Science › Statistics

Synonyms:

• difference
• discrepancy

Meaning: A version of something that differs from the original.

Part of speech: noun

Example: The new variant of the software includes several improvements.

Category: Science › Genetics

Synonyms:

• variation
• alternative

Meaning: A change or difference in condition, amount, or level.

Part of speech: noun

Example: There was a variation in the results of the experiment.

Category: Science › Statistics

Synonyms:

• change
• diversity

Antonyms:

• uniformity
• sameness

Meaning: A quantity with both direction and magnitude.

Part of speech: noun

Example: In physics, a vector can represent force.

Category: Science › Mathematics

Synonyms:

• direction
• magnitude

Meaning: a small, fast dinosaur

Part of speech: noun

Example: The velociraptor was known for its speed.

Category: Science › Paleontology

Synonyms: dinosaur

Meaning: the speed of something in a given direction

Part of speech: noun

Example: The velocity of the car increased as it went downhill.

Category: Science › Physics

Synonyms:

• speed
• rate

Antonyms: slowdown

Meaning: the second planet from the sun

Part of speech: noun

Example: Venus is often called Earth's twin.

Category: Science › Astronomy

Synonyms: planet

Meaning: to confirm the truth or accuracy

Part of speech: verb

Example: Please verify your email address.

Category: Science › Verification

Synonyms:

• confirm
• validate

Antonyms:

• disprove
• deny

Meaning: A container, especially one used for holding liquids.

Part of speech: noun

Example: She poured the water into the vessel.

Category: Science › Chemistry

Synonyms:

• container
• holder