IPA: /ˌtræn.zəˈtlæn.tɪk/
KK: /trænˈzæt.læntɪk/
Relating to or located on the other side of the Atlantic Ocean.
The transatlantic flight took over eight hours.
Transatlantic → It is formed from "trans-" (meaning across) and "Atlantic" (from Latin "Atlantis", referring to the Atlantic Ocean). The word describes something that crosses or spans the Atlantic Ocean.
Picture something that goes 'across' ('trans-') the vast 'Atlantic' Ocean — that's what transatlantic means.
No commonly confused words.