[...] The relation of modifying, whereby one element ʻmodifiesʼ another, is not the only relationship that may obtain the members of a complex. Where one element modifies another, the status of the two is unequal. The modifying element is dependent on the modified. But two elements may be joined together on an footing, neither being dependent on the other. The general term for the modifying relation is HYPOTAXIS. Hypotaxis is the relation between a dependent element and its dominant, the element on which it is dependent. Contrasting with this is PARATAXIS, which is the relation between two like elements of equal status, one initiating and the other continuing.
- Halliday (1985), a pag.195

Parataxis and hypotaxis are general relationships which are not restricted to the rank of the clause. They define complexes at any rank: clause complex, group or phrase complex, ord complex [...] Parataxis is the linking of elements of equal status. Both the initiating and the continuing element are free, in the sense that each could stand as functioning whole. Hypotaxis is the binding of elements of unequal status. The dominant element is free, but the dependent element is not.
- Halliday (1985), a pag.198

Parataxis and hypotaxis are the two basic forms taken by logical relations in natural language. The terms in a logico-semantic relation are ordered by them as either equal (paratactic) or unequal (hypotactic).
- Halliday (1985), a pag.202