A chromosomal complement with at least three complete sets of homologous chromosomes

The sentence probably saying about polyploid

Polyploid is when the cell duplicates a complete set of chromosome. This will result in one extra chromosome for each kind which makes them triploid, tetraploid or more. The polyploid organism will more likely to die. In the animal, the extra chromosome will cause sexual imbalance and can make it infertile.