lightweight

Etymology

From light (“not heavy”, adjective) + weight (noun).

noun

1. (combat sports) A particular weight class, or member of such, as prescribed by the rules, between that of the heavier welterweight and the lighter featherweight. See Wikipedia for the specifics of each sport.
2. (rowing) A particular weight category as prescribed by the rules, separate from an open or heavyweight class.
3. (weightlifting) A competitive weight division as prescribed by the rules, between the heavier middleweight and the lighter featherweight.
4. One of little consequence or ability.
5. A person who cannot handle their drink; one who gets drunk on very little alcohol.
   1. (by extension) A person with low endurance.
6. A political candidate with little chance of winning

adj

1. Lacking in earnestness, ability, or profundity
2. Having less than average weight
   For example, lightweight construction and Jacobs bogies save weight, and a lighter train uses less power. May 19 2021, David Clough, “Swiss precision meets UK growth”, in RAIL, number 931, page 57
3. Lacking in strength
   With the Gunners far too lightweight in midfield, Mikel Arteta dropped back into a deeper-lying role. This freed Yossi Benayoun to go further forward, a move that helped forge a rare Arsenal chance on 30 minutes when the Israeli released Van Persie, only for the Dutchman's snap-shot to be tipped around the post. September 13, 2011, Sam Lyon, “Borussia Dortmund 1 - 1 Arsenal”, in BBC
4. (computing) Having a small footprint or performance impact

verb

1. (transitive) To reduce the amount or weight of.
   By extending the producer’s responsibility to the product’s disposal (its post-consumer life), issues previously outside the business calculus become of paramount importance. Because a producer knows it will have to bear the cost of collecting and valorizing the product, it must manage a new set of business matters. Can the packaging be lightweighted? Are the materials all recyclable? 22 December 1997, James Salzman, “Sustainable consumption and the law”, in Environmental Law
   The solar photovoltaic array, GPS antennae and telephony antenna all would be lightweighted and integrated into the balloon structure, and the sensor-module would be ruggedized and miniaturized. 2002, Edward Teller, Cecil Leith, Gregory Canavan, Lowell Wood, “Long-Range Weather Prediction III: Miniaturized Distributed Sensors for Global Atmospheric Measurements”, in A. Zichichi, R. Ragaini, editors, International Seminar on Nuclear War and Planetary Emergencies, 26th Session (The Science and Culture Series: Nuclear Strategy and Peace Technology), World Scientific, page 328
   According to Klausner, “lightweighting” all cars and planes in the US would save 121 billion litres of fuel a year and cut carbon emissions by about 5 per cent. 28 February 2015, Hal Hodson, “Heavy metal is so last year”, in New Scientist, page 23