something that has a similar position, structure, value, or purpose to something else

Chronic fatigue syndrome has had its homologues for many years, including such poorly described disease states as neurasthenia. 多年来一直存在慢性疲劳综合征的同源症，包括神经衰弱等描述不清的疾病状态。

I was reminded of the many similarities with the American Civil War of 1861-65: not just the death toll, but the homologue of Oxford and Richmond, Virginia, as doomed capitals. 这让我想起了1861-1865年美国内战的许多相似之处: 不仅是死亡人数，而且是牛津和弗吉尼亚里士满的相对应之处，这两个在劫难逃的首府。

something that has the same origin as something else but now has a different purpose or shape as a result of evolution (= gradual change over millions of years)

Connections between visual and cerebellar regions are putative human homologues of connections in the macaque brain. 据推定，猕猴大脑视觉区跟小脑区间的纽带是人类对应部位的同源异型体。

a chromosome (= a rod-like structure in cells, containing the chemical patterns that control what an animal or plant is like) that contains similar information to another chromosome that it forms a pair with during meiosis (= a type of cell division)

A diploid cell contains two of each type of chromosome, one homologue from the mother and one homologue from the father. 一个二倍体细胞中，每一种类型的染色体都含有两条，一条同源染色体来自母体，一条同源染色体来自父体。