Definitions For A

noun

• A United States territory on the eastern part of the island of Samoa
• A very poisonous metallic element that has three allotropic forms; arsenic and arsenic compounds are used as herbicides and insecticides and various alloys; found in arsenopyrite and orpiment and realgar
• The blood group whose red cells carry the A antigen
• The 1st letter of the Roman alphabet
• The basic unit of electric current adopted under the Systeme International d'Unites
• A metric unit of length equal to one ten billionth of a meter (or 0.0001 micron); used to specify wavelengths of electromagnetic radiation
• (biochemistry) purine base found in DNA and RNA; pairs with thymine in DNA and with uracil in RNA
• One of the four nucleotides used in building DNA; all four nucleotides have a common phosphate group and a sugar (ribose)
• Any of several fat-soluble vitamins essential for normal vision; prevents night blindness or inflammation or dryness of the eyes
• The first letter of the English alphabet
• A musical note or key referred to by the letter A : the sixth tone of a C-major scale
• A grade that is given to a student for doing excellent work

adverb

• To the same degree (often followed by as')