Common Core Standards
Grade 5
Reading RF.5.3.A
Use combined knowledge of all letter-sound correspondences, syllabication patterns, and morphology (e.g., roots and affixes) to read accurately unfamiliar multisyllabic words in context and out of context.
In other words, your students should be able to identify and break down the meaning of "unfamiliar multisyllabic words" such as...well..."multisyllabic." This is a skill that students have already begun developing, so the drive here is to exercise their existing skills with a higher and more complex level of vocabulary.