In English grammar, an abstract noun is a noun or noun phrase that names an idea, event, quality, or conceptâfor example, courage, freedom, progress, love, patience, excellence, and friendship. An abstract noun names something that can't be physically touched. Contrast with concrete noun.
The adult human brain weighs on average about 1.2â1.4 kg (2.6â3.1 lb), or about 2% of total body weight, with a volume of around 1260 cm3 in men and 1130 cm3 in women, although there is substantial individual variation.
The average human brain weighs about 1360 grams, or 3 lbs. Thatâs about four times lighter than an elephant brain. The heaviest mammalian brain is found in the sperm whale â weighing 7711 grams (17 lbs). Larger brains are needed, in part, to control larger muscles. At the other end of the scale is the owl brain that weighs just over two grams. A bullfrog's brain is about one-tenth smaller than that.