What does pairwise mean?
Pairwise means involving two people, things, or elements at a time, usually in a comparison or a set of relationships. For example, a pairwise comparison measures how two candidates or options relate to each other, while a pairwise distance records the separation between each two points in a set. The term is especially important in mathematics, statistics, computer science, biology, and academic research, where relationships are often assessed one pair at a time. In a set of three items, for instance, pairwise comparison involves three comparisons: one for each combination of two. Although pairwise can broadly suggest mutuality, it is more precise when describing a process or calculation that treats every two-member combination separately. Its technical character makes it more common in formal and specialized writing than in everyday speech, where mutual, reciprocal, or side-by-side may be more natural.
Involving or comparing two people, things, or elements at a time; relating to each pair in a set.
"The model uses a pairwise penalty to discourage excessive differences between related items."
Especially common in mathematical, statistical, scientific, and computer-science contexts.
In a way that involves or compares two people, things, or elements at a time.
"The two methods were compared pairwise across repeated trials."
Less frequent than the adjective, but standard in technical and academic writing.
Pairwise is the language of systems that compare every possible combination: in a set of three, there are three pairwise comparisons.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Words that share this root
Related word forms
How pairwise is actually used
The adjective is formal and technical, especially common in statistics, mathematics, computer science, and academic writing. It is less usual in everyday conversation than words such as "mutual" or "reciprocal".
Easily confused with pairwise
A pair is a group of two; pairwise describes a relationship, comparison, or operation involving two members at a time.
Reciprocal means involving mutual exchange or response, whereas pairwise more precisely means involving each pair of members in a set.