An. the blood group whose red cells carry the A antigen ; An. the 1st letter of the Roman alphabet ; An. the basic unit of electric current adopted under the Systeme International d'Unites ; An. a metric unit of length equal to one ten billionth of a meter (or 0.0001 micron) ; used to specify wavelengths of electromagnetic radiation ; An. (biochemistry) purine base found in DNA and RNA ; pairs with thymine in DNA and with uracil in RNA ; An. one of the four nucleotides used in building DNA ; all four nucleotides have a common phosphate group and a sugar (ribose) ; An. any of several fat-soluble vitamins essential for normal vision ; prevents night blindness or inflammation or dryness of the eyes ; A batteryn. the battery used to heat the filaments of a vacuum tube ; a bitadv. to a small degree ; somewhat ; a capellaadj. sung without instrumental accompaniment ; a capellaadv. without musical accompaniment ; a capella singingn. singing without instrumental accompaniment ; a cappellaadj. sung without instrumental accompaniment ; a cappellaadv. without musical accompaniment ; a cappella singingn. singing without instrumental accompaniment ;
