(mathematics) an inverse proportion, a reciprocal ratio

(mathematics) to be in inverse ratio, to be inversely proportional

(algebra) variable / (computing) variable

two things [small or without a counter category]

relationship, relation / involvement, participation / personal connection, family relationship / romantic relationship

be related / be romantically involved

(idiomatic) as alike as two peas in a pod, very similar (often of family members)

(idiomatic) people as alike as two peas in a pod, very similar (often of family members)

alias; nickname

(split) into exactly two equal parts