a-

漢語翻譯pref. 不, 缺少, 無
【醫(yī)】 不, 無, 缺; 離英語解釋：名詞 a-:

1. a metric unit of length equal to one ten billionth of a meter (or 0.0001 micron); used to specify wavelengths of electromagnetic radiation

   同義詞：angstrom, angstrom unit, A

2. any of several fat-soluble vitamins essential for normal vision; prevents night blindness or inflammation or dryness of the eyes

   同義詞：vitamin A, antiophthalmic factor, axerophthol, A

3. one of the four nucleotides used in building DNA; all four nucleotides have a common phosphate group and a sugar (ribose)

   同義詞：deoxyadenosine monophosphate, A

4. (biochemistry) purine base found in DNA and RNA; pairs with thymine in DNA and with uracil in RNA

   同義詞：adenine, A

5. the basic unit of electric current adopted under the Systeme International d"Unites

   同義詞：ampere, amp, A

6. the 1st letter of the Roman alphabet

   同義詞：A, letter a

7. the blood group whose red cells carry the A antigen

   同義詞：A, type A, group A