trans-
pref.1. Across; on the other side; beyond: transpolar.
2. Through: transcontinental.
3. Change; transfer: transliterate.
4. Having a pair of identical atoms on opposite sides of two atoms linked by a double bond. Used of a geometric isomer: trans-butene.
[From Latin trāns-, from trāns, across, beyond, through; see terə-2 in the Appendix of Indo-European roots.]