Pronunciation: [tˈaɡ ˈɒf] (IPA) 
The phrase "tag off" is spelled with the phonetic transcription /tæɡ ɒf/. The first syllable is pronounced with a short "a" sound, like "cat". The "g" sound in the second syllable is a hard "g", like in "dog". The final two letters, "of", are pronounced with the same sound as the word "off." "Tag off" is a common expression used in games like tag or others where players must take turns or switch roles.
Tag off (verb):
To complete an action by scanning or tapping a digital or physical tag in order to register exit or termination of an activity, usage, or journey.
When referring to transportation systems, "tag off" specifically describes the process of ending a journey or trip on a contactless card, such as a smartcard or RFID-enabled ticket, by tapping it onto a designated reader to record the end of the travel. The tag off action typically deducts the appropriate fare from the passenger's card balance or determines the final distance travel, allowing for an accurate fare calculation. It is common in systems that employ cashless systems or electronic ticketing where passengers use a reusable card or token to access and pay for transportation.
The practice of tagging off is prevalent in various modes of public transportation, including buses, trains, trams, and subways, where it helps to ensure appropriate fare payment, informs transportation authorities about passenger flows, and facilitates accurate accounting and financial management of the transport system. Tagging off is typically required to be done at the end of a journey or when exiting the transportation network to prevent potential fare evasion or overcharging. It is an essential process for commuters and travelers using contactless ticketing or smartcard-based systems to properly complete their journey and maintain the accuracy and efficiency of transportation fare systems.
The term "tag off" does not have a distinct etymology as it is a phrasal verb comprised of the word "tag" and the particle "off". However, we can look at the etymology of the individual components:
1. Tag: The word "tag" dates back to the late 14th century and its origin is uncertain. It is believed to be related to the Middle Low German word "tagge", meaning "day". Over time, the meaning of "tag" expanded to include various concepts such as a metal attachment or small label. In the context of "tag off", it generally refers to a process of touching an electronic card or device to indicate the end of an action, such as leaving a public transportation system.
2. Off: The word "off" goes back to Old English, derived from the Proto-Germanic word *af (meaning "from" or "away").
