noun
General term for woody plants smaller than trees, with multiple stems.
庭に灌木を植えた。
I planted a shrub in the garden.
その鳥は灌木の陰に隠れた。
The bird hid behind the bush.
低木 is a more technical term for 'shrub' or 'low tree', often used in botany and forestry, while 灌木 is a common word for 'bush' or 'shrub' in everyday language.
Compound of 灌 (かん, 'to pour water') and 木 (ぼく, 'tree'), referring to plants that grow low and bushy, often near water. The exact historical derivation is uncertain.