From Middle English gayn, gain, gein (“profit, advantage”), from Old Norse gagn (“benefit, advantage, use”), from Proto-Germanic *gagną, *gaganą (“gain, profit", literally "return”), from Proto-Germanic *gagana (“back, against, in return”), a reduplication of Proto-Germanic *ga- (“with, together”), from Proto-Indo-European *ḱóm (“next to, at, with, along”). Cognate with Icelandic gagn (“gain, advantage, use”), Swedish gagn (“benefit, profit”), Danish gavn (“gain, profit, success”), Gothic 𐌲𐌰𐌲𐌴𐌹𐌲𐌰𐌽 (gageigan, “to gain, profit”), Old Norse gegn (“ready”), dialectal Swedish gen (“useful, noteful”), Latin cum (“with”); see gain-, again, against. Compare also Middle English gaynen, geinen (“to be of use, profit, avail”), Icelandic and Swedish gagna (“to avail, help”), Danish gavne (“to benefit”).

The Middle English word was reinforced by Middle French gain (“gain, profit, advancement, cultivation”), from Old French gaaing, gaaigne, gaigne, a noun derivative of gaaignier (“to till, earn, win”), from Frankish *waidanjan (“to pasture, graze, hunt for food”), ultimately from Proto-Germanic *waiþiz, *waiþō, *waiþijō (“pasture, field, hunting ground”); compare Old High German weidōn, weidanōn (“to hunt, forage for food”) (Modern German Weide (“pasture”)), Old Norse veiða (“to catch, hunt”), Old English wǣþan (“to hunt, chase, pursue”). Related to wathe, wide.

gain (third-person singular simple present gains, present participle gaining, simple past and past participle gained)

(transitive) To acquire possession of.

(transitive, dated) To come off winner or victor in; to be successful in; to obtain by competition.

to gain a battle; to gain a case at law

(transitive) To increase.

(intransitive) To be more likely to catch or overtake an individual.

I'm gaining (on you).

gain ground

(transitive) To reach.

to gain the top of a mountain

In glaciology, an ice cap is a mass of ice that covers less than 50,000 km2 (19,000 sq mi) of land area (usually covering a highland area). Larger ice masses covering more than 50,000 km2 (19,000 sq mi) are termed ice sheets.

Ice sheets are bigger than ice shelves or alpine glaciers. Masses of ice covering less than 50,000 km2 are termed an ice cap.

Mass crystallization is the nucleation and growth of a large number of usually small crystals (~10−3–10−1 cm) in one and the same area of space. Examples of it are the formation of metal ingots and kidney stones, the solidification of concrete, and the production of granulated fertilizers, medicines, sugar, and salt.

At the present day, ultrafine soot particles have become the object of increasing attention due to their well-documented adverse effects on human health and climate. In particular, understanding soot nucleation is one of the most challenging problems toward a more controlled and cleaner combustion. Detailed information on the chemistry of nascent soot particles (NSPs) is expected to provide clues on the soot formation and growth reaction pathways. Herein, the early steps of soot formation in flames are addressed by investigating the chemical composition of NSPs and their molecular precursors by secondary ion mass spectrometry.