There are multiple definitions:

1. ascorbic acid free(English)

   • Diet, Vitamin
   • https://pubchem…id#section=Uses

2. 2-acetamidofluorene(English)

   • aromatic compound
   • Biochemistry
   • https://cancerr…/8/376.full.pdf

3. alternative allele frequency(English)

   • percentage of reads supporting the alternative allele among all simulated reads covering a variant
   • GWAS
   • Genomics
   • https://www.bio…s.org/p/190931/

4. N-acetoxy-acetylaminofluorene(English)

5. amino acid formula(English)

   • CMA, GERD
   • Diet, Mouth, esophagus and stomach
   • https://doi.org…3390/nu13082762