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 adult human brain weighs about 3 pounds â the same weight as the average brain of a dolphin (which is also a very intelligent animal). But there are animals with larger brains that are not considered to be as intelligent as a dolphin. For instance, a sperm whale has a brain that weighs about 17 pounds.