Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
transūmo or trans-sūmo, ĕre, v. a., to take from one to another; to adopt, assume (poet. and post-Aug.): hastam laevā, Stat. Th. 3, 292: mutatos cultus, id. ib. 2, 242.