total number of bands estimated to be present in a haplotype set (23) of
chromosomes. When cell division is arrested and staining is performed at
an earlier stage of mitosis (prometaphase), chromosomes appear longer, with
approximately 700-1200 bands. At a later stage of mitosis (metaphase), chromosomes
are more condensed, with approximately 300-600 bands; at higher band levels,
the greater resolution increases the ability to identify more subtle chromosomal
abnormalities and their breakpoints.
Definition from: GeneReviews
from the University of Washington and the National Center for Biotechnology Information
See also Understanding Medical Terminology.