triplex noun 5adjective 3verb 1forms 3 noun5 •A building with three apartments or divisions. •A dwelling unit with three floors. •Anything with three parts.In a recent paper on homopyrimidine decamers containing aeg-monomers and thymine monomers with a sulfomethyl substituent at the γ-position, similar triplexes has also been described [43 ]. — 2015 •A throwing motion where three balls are thrown with one hand at the same time. •Triple time. adjective3 •Having three parts; triple or threefold. •Having three floors. •Having three units, divisions, suites, apartments. verb1 •To make triplex. formstriplexed · triplexing · triplexes