Merriam-Webster Inc. has added more than 100 new entries to its new edition of the Collegiate Dictionary. Here are some, along with the year in which Merriam-Webster first found them used in an English-language publication:

Air quotes (1989): gesture made by raising and flexing the index and middle fingers of both hands, used to call attention to a spoken word or expression.

Dark energy (1998): hypothetical form of energy that produces a force that opposes gravity and is thought to cause the accelerating expansion of the universe.

Dirty bomb (1956): bomb designed to release radioactive material.

Dwarf planet (1993): celestial body that orbits the sun and has a spherical shape, but is too small to disturb other objects from its orbit.

Edamame (1951): immature green soybeans, usually in the pod.

Fanboy (1919): boy who is an enthusiastic devotee, such as of comics or movies.

Infinity pool (1992): outdoor swimming pool with an edge over which water flows into a trough, but seems to flow into the horizon.

Jukebox musical (1993): musical that features popular songs from the past.

Kiteboarding (1996): the sport of riding on a small surfboard propelled across water by a large kite, to which the rider is harnessed.

Malware (1990): software designed to interfere with a computer’s normal functioning.

Mental health day (1971): day that an employee takes off from work to relieve stress or renew vitality.

Mondegreen (1954): word or phrase that results from a mishearing of something said or sung. From the mishearing in a Scottish ballad of “laid him on the green” as “Lady Mondegreen.”

Netroots (2003): grassroots political activists who communicate via the Internet, especially by blogs.

Norovirus (2002): any of a genus of small round single-stranded RNA viruses; specifically, Norwalk virus.

• Pescatarian (1993): vegetarian whose diet includes fish.

Phytonutrient (1994): bioactive, plant-derived compound (as resveratrol) associated with positive health effects.

Pretexting (1992): presenting oneself as someone else to obtain private information.

Prosecco (1881): a dry Italian sparkling wine.

Racino (1995): racetrack at which slot machines are available for gamblers.

Soju (1978): a Korean vodka distilled from rice.

Subprime (1995) I: having or being an interest rate that is higher than a prime rate and is extended especially to low-income borrowers; 2: extending or obtaining a subprime loan.

Supercross (1983): motorcycle race held in a stadium on a dirt track having hairpin turns and high jumps.

Texas Hold ’em (1995): Poker in which each player is dealt two cards face down and all players share five cards dealt face-up.

Webinar (1998): live, online educational presentation during which participating viewers can submit questions and comments.

Wing nut (circa 1900): Slang: one who advocates extreme measures or changes; radical.

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