ナビゲーター

〈事こと〉のナビゲーターを務つとめるto serve as the host/navigator of something
彼かの女じょはこの旅たび番ばん組ぐみのナビゲーターを務つとめている。
She serves as the host of this travel program.
助じょ手しゅ席せきでナビゲーターをするto act as navigator (co-driver) from the passenger seat
ラリーでは助じょ手しゅ席せきでナビゲーターをする人ひとがいる。
In rallying, there's a person who acts as navigator from the passenger seat.

Related words

案あん内ない人にん sense 1
案内人 is the traditional Japanese term for a guide who leads the way, while ナビゲーター is a modern loanword covering the same role plus media and device contexts.
司し会かい者しゃN3sense 2
司会者 is the standard word for an MC who mainly keeps an event running smoothly, while ナビゲーター in the media sense suggests a more explanatory, guiding presence.
ガイドN2sense 1
ガイド typically refers to a tour guide who explains and leads visitors, while ナビゲーター emphasizes plotting or directing a course, as in rallying or navigation devices.
進しん行こう役やく sense 2
進行役 focuses narrowly on moving a program or meeting along, whereas ナビゲーター also implies steering the audience's understanding of the content.
ナビ
ナビ is the casual shortened form used for a person who gives directions (e.g., in a rally car), while ナビゲーター is the fuller, more formal word for the same role.

ナビゲーターUsage79%
Standard katakana spelling; the most common form.
ナビゲータUsage21%
Alternate spelling without the long vowel; less common but still used.

Borrowed from English 'navigator'.