noun

1. the moon, in its first or last quarter, when only half the face is illuminated
2. anything shaped like a crescent, especially the base of a fingernail

proper noun

1. A very bright comet which can be seen every 75-76 years.

abbreviation

1. (parachuting) High Altitude, Low Opening.
   

   When you have enough experience, you can do a HALO jump.

adjective

1. Of or relating to the sun, especially rising and setting with the sun.

adjective

1. (astronomy) having the sun at the center/centre; usually in reference to a solar system or orbit

noun

1. An apparatus for signalling by means of a moveable mirror which reflects flashes of sunlight.
2. A heliogram.
3. An instrument for measuring the intensity of sunlight.
4. A device for photographing the sun.
5. (obsolete) A photograph.

verb

1. (transitive) To send a message by heliograph.
2. (intransitive) To send a heliograph.

noun

1. (astronomy) The boundary of heliosphere where the Sun's solar wind is stopped by the interstellar medium.

proper noun

1. (greekmyth) Son of Jupiter and Alcmene, a celebrated hero who possessed exceptional strength. Most famous for his 12 labors performed to redeem himself after killing his family.
2. (constellation) A summer constellation of the northern sky, said to resemble the mythical hero. It lies between the constellations Lyra and Corona Borealis.
3. (astronomy) A crater in the first quadrant on the moon.

proper noun

1. (Greek mythology) the herald and messenger of the gods, and the god of roads, commerce, invention, cunning, and theft.

noun

1. (star): a plot of the absolute magnitude of stars versus their colour (or surface temperature); shows the main sequence of stars plus the white dwarfs and red giants

noun

1. The horizontal line that appears to separate the Earth from the sky.
2. The range or limit of one's knowledge, experience or interest.
3. (geology) A specific layer of soil or strata

noun (horns, -)

1. (countable) A hard growth of keratin that protrudes from the top of the head of certain animals.
2. (uncountable) The hard substance from which animals' horns are made, sometimes used by man as a material for making various objects.

an umbrella with a handle made of

1. (countable) Any of several musical wind instruments.
2. (countable) An instrument resembling a musical horn and used to signal others.

hunting

1. (countable) A loud alarm, especially one on a motor vehicle.
2. (countable) A conical device used to direct waves.

antenna

loudspeaker

1. (context, informal, countable) Generally, any brass wind instrument.
2. (context, slang, countable, from the horn-shaped earpieces of old communication systems that used air tubes) A telephone.
3. (context, uncountable, coarse, slang, definite article) An erection of the penis.
4. (context, countable, coarse, slang, definite article) A peninsula or crescent-shaped tract of land. "to navigate around the horn."

noun (context, singulare tantum)category:English nouns

1. alternative spelling of Hubble constant

noun (context, singulare tantum)category:English nouns

1. alternative spelling of Hubble law

noun the

1. The full moon after the Harvest Moon.

proper noun

1. (astronomy) An open cluster of stars in the constellation Taurus, and the nearest visible such cluster to Earth.
2. (greekmyth) Daughters of the Titan Atlas and sisters of the Pleiades.

proper noun

1. (constellation) A winter constellation of the southern sky, said to resemble a small serpent. It lies between the constellations Mensa and Tucana. It is not to be confused with the constellation Hydra.

proper noun

1. (Greek mythology) A Titan, the son of Gaia and Uranus and the father of Helios, Selene and Eos.