Glossary
Definition: Jet lag is a temporary sleep disorder caused by rapid travel across multiple time zones, resulting in fatigue, insomnia, difficulty concentrating, and digestive issues as your body’s circadian rhythm adjusts to the new time zone.
Last updated
Term at a glance
| Term | Jet Lag |
|---|---|
| One-liner | Jet lag is a temporary sleep disorder caused by rapid travel across multiple time zones, resulting in fatigue, insomnia, difficulty concentrating, and digestive issues as your… |
| Where it matters | Premium-cabin booking decisions, fare-rules interpretation, airline-product comparison. |
| Related concepts | Circadian Rhythm · Lie-Flat Seat · Red-Eye Flight · Boeing 787 Dreamliner · Business Class |
| Last verified | 2026-05-07 |
Jet lag occurs because your body’s internal clock (circadian rhythm) is still synchronised with your departure time zone. Symptoms are worse when flying east (where you "lose" time) than when flying west, and generally take one day per time zone crossed to fully recover.
Common jet lag symptoms include: daytime fatigue, difficulty sleeping at night, impaired concentration, irritability, digestive problems, and general malaise. For business travellers who need to perform immediately upon arrival, jet lag can significantly impact productivity.
Business class significantly mitigates jet lag’s impact. Lie-flat seats allow proper sleep during overnight flights, arriving rested rather than exhausted. Modern aircraft like the 787 Dreamliner and A350 further help with higher cabin pressure and humidity. Some airlines offer jet lag management advice, and premium cabin meals are often designed to support natural sleep cycles. BookMyBusinessClass prioritises getting clients into lie-flat business class for exactly this reason.
In booking practice
At a Glance
| Term | Quick definition | Reference |
|---|---|---|
| Interline | An interline agreement is an arrangement between two or more airlines to handle passengers travelling on… | Read |
| Joint Business (JB) / Joint Venture (JV) | A deeper commercial arrangement than codeshare alone, where partner airlines coordinate scheduling, capacity,… | Read |
| In-Flight Entertainment (IFE) | In-flight entertainment (IFE) is the onboard system providing movies, TV shows, music, games, and other media… | Read |
| Joint Venture (Airline JV) | A formal commercial agreement between airlines (often within an alliance) to coordinate schedules, share… | Read |
| IATA | IATA (International Air Transport Association) is the global trade association for airlines, representing… | Read |
| K-ETA (Korea Electronic Travel Authorization) | An electronic travel authorization required for visa-free entry into South Korea by most Western… | Read |
Related Terms
An interline agreement is an arrangement between two or more airlines to handle passengers travelling on itineraries that involve flights on multiple carriers, including through-checked baggage and coordinated rebooking during disruptions.
A deeper commercial arrangement than codeshare alone, where partner airlines coordinate scheduling, capacity, and revenue on a corridor under regulatory antitrust immunity. The major transatlantic Joint Businesses (oneworld AA-BA-IB-AY-EI, SkyTeam DL-AF-KL-VS, Star Alliance UA-LH-AC) are the principal commercial structures shaping premium-cabin booking on those corridors.
In-flight entertainment (IFE) is the onboard system providing movies, TV shows, music, games, and other media to passengers, typically via personal seatback screens in premium cabins with noise-cancelling headphones.
A formal commercial agreement between airlines (often within an alliance) to coordinate schedules, share revenue, and operate as a single network on specific transcontinental corridors. JVs typically receive antitrust immunity from regulators, allowing deeper coordination than standard codeshare partnerships.
IATA (International Air Transport Association) is the global trade association for airlines, representing approximately 300 airlines comprising 83% of total air traffic. IATA sets industry standards for ticketing, safety, and operations.
An electronic travel authorization required for visa-free entry into South Korea by most Western nationalities since 2024. K-ETA pre-clearance is required online before departure for visa-exempt visits; transit passengers staying airside under 24 hours generally do not need K-ETA.
Drill deeper
FAQ
A specialist responds within 15 minutes — no account, no obligation, never a bot.