Similar words
transitar
transitar is more about passing through or along a route; viajar is more general travelling.
Similar in other languages
German
reisen
reisen is the German word for the same thing — both mean "to travel."
Portuguese
viajar
viajar is the Portuguese word for the same thing — both mean "to travel."
Practice
1 What does viajar mean?
to travel
2 Fill the gap: ___ por trabajo.
Full sentence: Viajo por trabajo. (I travel for work.)
3 Which fingerprint chart matches viajar?
viajar: neutral register, core frequency, general domain, neutral connotation.