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English Words Starting With A

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Noun Verb Adjective Adverb Plural noun Combining form Verb (transitive)Verb (intransitive)Verb (ambitransitive)

astronomical clock
nounC2
/ˌæstrəˈnɒmɪkl klɒk/A precision clock displaying astronomical information such as positions of the sun, moon, zodiacal constellations, and sometimes planetary motions.
astronomical distance
nounC1
/ˌæs.trəˈnɒm.ɪ.kəl ˈdɪs.təns/An extremely large distance, typically measured in space between celestial bodies.
astronomical frame of reference
nounC2
/ˌæs.trəˈnɒm.ɪ.kəl freɪm əv ˈref.ər.əns/A coordinate system used to specify the positions and motions of celestial objects in space.
astronomical telescope
nounC1
/ˌæs.trəˈnɒm.ɪ.kəl ˈtel.ɪ.skəʊp/A precise optical instrument specifically designed for observing distant celestial objects like stars, planets, and galaxies.
astronomical triangle
nounVery Low
/ˌæstrəˈnɒmɪkəl ˈtraɪæŋɡl̩/A spherical triangle formed on the celestial sphere by connecting the celestial pole, the zenith, and a celestial body (usually a star).
astronomical twilight
nounLow
/ˌæs.trəˈnɒm.ɪ.kəl ˈtwaɪ.laɪt/The period of twilight when the Sun is between 12 and 18 degrees below the horizon, during which the sky is very dark but not completely black, and faint stars become visible.
astronomical unit
nounC1+
/ˌæs.trəˈnɒm.ɪ.kəl ˈjuː.nɪt/A standard unit of measurement in astronomy, equal to the average distance from the Earth to the Sun, approximately 149.6 million kilometres (93 million miles).
astronomical year
nounC2
/ˌæstrəˈnɒmɪkəl jɪə/The time it takes for the Earth to complete one full orbit around the Sun, approximately 365.25636 days (a sidereal year).
astronomy
nounB2
/əˈstrɒnəmi/The scientific study of celestial objects (stars, planets, galaxies) and phenomena that originate outside Earth's atmosphere.
astrophile
nounC2/Rare
/ˈæstrə(ʊ)faɪl/A person who loves stars, astronomy, or celestial objects.
astrophotography
nounC1
/ˌæstrəʊfəˈtɒɡrəfi/Photography of astronomical objects and celestial events, such as stars, planets, and galaxies.
astrophotometry
nounVery Low
/ˌæstrəʊfəʊˈtɒmɪtri/The measurement of the intensity of light from celestial objects.
astrophysics
nounC1
/ˌæstrəʊˈfɪzɪks/The branch of astronomy that deals with the physical properties and processes of celestial objects and phenomena.
astrosphere
nounRare/Specialist
/ˈastrə(ʊ)sfɪə/A central structure in a dividing cell, specifically a star-shaped system of microtubules radiating from the centrosome; in astronomy, a rare term for the sphere of stars (celestial sphere).
astrotourism
nounLow frequency
/ˌæstrəʊˈtʊərɪzəm/Tourism focused on astronomical experiences and stargazing at destinations with dark skies.
astrotourist
nounLow
/ˈæstrəʊˌtʊərɪst/A person who travels specifically to view astronomical events or visit sites of astronomical significance, often in remote locations with dark skies.
astroturf
nounLow-medium
/ˈæstrəʊtɜːf/A brand of artificial grass, or synthetic turf used for sports fields and landscaping.
astroturfing
nounLow
/ˈæstrəʊˌtɜːfɪŋ/The practice of masking the sponsors of a message or organization to make it appear as though it originates from and is supported by grassroots participants.
asturian
adjectivenounC2
/æˈstjʊə.ri.ən/Relating to the region of Asturias in northern Spain, its culture, language, or people.
asturias
nounC2
/æˈstjʊə.ri.æs/An autonomous community and historical region in northern Spain.

Showing 7601–7620 of 8734 words.