“ … ile, beraber, birlikte, müşterek, ortak, iştirak eden, bağlaşık, müttefik”. Bu önekle yapılan bazı
sözcükler şunlardır: (Bunların anlamları öneksiz sözcükten çıkarılabilir):
coadministration, coadmire, coadmit, coadventure, coagent, coagitate, coambassador, coanimate, coappear, coapprove, coarrange, coassist, coassume, coattend, coattest, coauditor, coauthor, coconnection, coconspirator, cocontractor, cocreate, codefendant, codiscoverer, coeditor, coestablish, coexecutor, coheir, coheritage, coindicate, coinfer, coinhabit, coinheritance, coinspire, coinventor, colaborer, comourner, co-occupy, co-organize, co-owner, copartner, coplaintiff, coresidence, cotrustee.
Prefix