noun
cohomology
A mathematical concept in algebraic topology and related fields; a dual notion to homology.
コホモロジー群は位相空間の不変量の一つだ。
Cohomology groups are one of the invariants of topological spaces.
Homology is a related concept; cohomology is its dual, often carrying additional algebraic structure such as a cup product.
From English 'cohomology', a mathematical term formed from 'co-' (dual) + 'homology'.