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 brain of an elephant weighs 4.5â5.5 kg (10â12 lb) compared to 1.6 kg (4 lb) for a human brain. While the elephant brain is larger overall, it is proportionally smaller. At birth, an elephant's brain already weighs 30â40% of its adult weight.