Itinerary is a noun.
An itinerary is another word for your schedule with a travel provider. For example, an airline reservation comes with an itinerary which lists your flights, dates, and times. An outbound itinerary specifically lists the first part of a round-trip travel reservation. For example, if you were flying from Minneapolis to Denver on one day and then flying from Denver back to Minneapolis on the next day, only the Minneapolis to Denver flight would be listed on the outbound itinerary. The return part of the trip would be listed on the return itinerary.
The part of speech for this particular word is a noun.
part of speech
The part of speech for "answer" is a noun.
what part of speech is beneath
adverb
Since an itinerary is a schedule of a trip, or voyage, it requires a list of things you are planning to do, and the time and date when you expect to do them, and also where you expect to do them. Since travel time is an important part of your schedule, scheduled departures and arrivals should be marked.
they are the same
The part of speech for "explicit" is an adjective.
The part of speech for "lecturer" is a noun.
The part of speech for "rapid" is an adjective.
The part of speech of "came" is a verb.