wild type

Short definition from Wiktionary

Noun

1. 1
   The typical form of an organism, strain, gene or characteristic as it occurs in nature.
2. 2
   The typical form of an organism, strain, gene or characteristic as it occurs in nature: The phenotype of the dominant allele (heterozygous genotype or homozygous dominant genotype).
3. 3
   Alternative spelling of wild type.