Definition of Dominant Trait. Before we can define exactly what a dominant trait is, we must first define and discuss many genetics terms. A gene, or unit of heredity, can have many different versions called alleles. There are often two kinds of alleles: Dominant allele: masks the effects of another allele; designated by an uppercase letter ; Recessive allele: effects are hidden by a dominant allele; designated by a lowercase letter ; Normally, individuals have two alleles for one gene: one from their mom and one from their dad.
Sydney is mostly a girls' name, but it is used for boys 4.31 percent of the time.
Sid and Sydney are the prominent related forms of Sidney listed in the Top 1000. Adoption of these boy names reached its most widespread during the years 1880-1889 (usage of 0.594%) and is now much less, with the forms Sid, Sidney and Sydney becoming less stylish.