Vinculum A vinculum is a bond or tie. In mathematics, a horizontal line over two or more terms can be used to show that they can be treated together; as if they were enclosed by parenthesis.
Hibernaculum In zoology, a hibernaculum (winter residence) is the location chosen by an animal for hibernation The word derives from the Latin hibernare (to spend the winter), which has its roots in the Indo-European ghei (winter) that is also the ancestor of words such as, chimera (a lamb that has live through one winter) and the Himalayas, from Sanskrit him (snow) + alaya (abode).
Backronym A "backronym" (or bacronym) is a phrase that is constructed "after the fact" from a previously existing initialism or acronym. The term is sometimes used to refer to the initialism or acronym itself but usually, it is a "replacement" backronym, the abbreviation already having an associated phrase. When the backronym phrase becomes more popular than the original, the word becomes an "anacronym."
Gegenschein A phenomenon that can be seen in very dark sky locations. A faint band of light appears on the ecliptic at a point that is opposite to the Sun's current position. It is the reflection of the Sun on dust in space
Ylem Ylem is a term which was used by George Gamow, Ralph Alpher and their associates in the late 1940's for a hypothetical original substance or condensed state of matter created after the bigbang, which became subatomic particles and elements as we understand them today.
Neologism A neologism is a word, term, or phrase which has been recently created often to apply to new concepts, to synthesise pre-existing concepts, or to make older terminology sound more contemporary.
Sastrugi Sastrugi or zastrugi are sharp irregular grooves or ridges formed on a snow surface by wind erosion and deposition, and found in polar and temperate snow regions.