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.
Credit: altrendo images Altrendo Getty Images. The human brain weighs about three times more than a chimpanzee's brain and is four and a half times smaller than the brain of an elephant. Albert Einstein had a smaller than average brain that only weighed about 2.7 pounds, but it had more glial cells than average. Humans have over 100 billion brain cells, and some of them survive an entire lifespan.