[1615–25; ‹ L substructiōn- (s. of substructiō) foundation, equiv. to substruct(us), ptp. of substruere to lay a foundation (sub- sub- + struc-, var. s. of struere to arrange, put in order + -tus ptp. suffix) + -iōn- -ion]This word is first recorded in the period 1615–25. Other words that entered Englishat around the same time include: berth, evolution, scintillation, synchronize, trigger-ion is a suffix, appearing in words of Latin origin, denoting action or condition, usedin Latin and in English to form nouns from stems of Latin adjectives (communion; union), verbs (legion; opinion), and esp. past participles (allusion; creation; fusion; notion; torsion)