A base is:

• in mathematics:
  • A number that is raised to a power, or base of an exponential function. This finds common use, for example, in the depiction of numbers, for instance, 10 is the base used in the decimal system, whereas 2 is the base in the binary numeral system. See also numeral system, radix and table of bases.
  • The base of a logarithmic function.
  • One of the parallel sides of a trapezoid or the unequal side of an isosceles triangle.
  • In topology, a base (topology) for a topology is a set of open sets such that every element of the topology is a union of the base sets. See also subbase.
  • Base of a transform in mathematics
• In politics, a base is a political party's core group of voters.
• In baseball, a base is one of 4 bags or plates placed at corners of the infield diamond that a player has to run to after hitting the ball.
• In a transistor the base is the controlling connection to the junction.
• In Marxism describes the material equipment and material relations of human society, as distinct from the 'superstructural' forms of society - laws, customs, ideas, beliefs, etc.
• BASE jumping is an extreme variation on skydiving.
• The name of the terrorist group Al-Qaida translates as "the base."
• In 2001, the catchphrase "All your base are belong to us" swept across the Internet.
• In chemistry, a base is the reactive complement to an acid. See Acid-base reaction theories.
• In genetics, a base pair consists of two complimentary DNA or RNA nucleotides joined by hydrogen bonds.
• In linguistics, a base is a synonym for root word.
• In telecommunications, Base is a mobile telephony company in Belgium, a subsidiary of the Dutch telecommunications company KPN.
• An isolated settlement in inhospitable conditions that must rely on outside help in order to survive, such as Antarctica base or Moon base .
• In architecture the lower, supporting part of a column. See base (architecture).
• An easily-confused homonym for Bass (musical term) , referring to various usages of bass and to bass, the vocal range.
• As modified by the word tax, it refers to how much income and assets one has, earns, spends, inherits, etcetera as used in the formula to decide owed tax (example: owed_tax = (base times tax_percent) minus deductible).