本能
ほんのう · honnou · JLPT N1 · noun
instinct
🐣 本 (root) + 能 (ability): an ability rooted in your nature = instinct
The same 本 as 日本 (origin, root), plus 能 (ability). Instinct is ability you are born with, like a newly hatched chick pecking at food without any lessons.
本 — tree 木 + mark at base
本 is a pictograph of a tree (木) with a stroke at its base, marking the roots. From this 'root' meaning it extended to 'origin,' 'source,' and 'foundation.' In modern usage it also serves as a measure word for bound objects like books.
能 — 厶 (head) + 月 (body/flesh) + 匕匕 (legs)
Originally a pictograph of a bear, showing its head, body, and powerful legs. Because bears were seen as strong and capable, the character was borrowed to mean 'ability' or 'can'. A new character 熊 (with the fire radical 灬) was later created for 'bear'.