One picture can hold both meanings: a person who gives you the impression of a thing instead of the thing itself. A mimic gives you the impression of a famous person — the voice, the pauses, the habits, not the person. An Impressionist painter gives you the impression a scene makes on the eye in one moment — the light and the colour, not every leaf. This is a way of holding the two together while you learn them; it is not a claim that one meaning grew out of the other.
From the word’s history
Both meanings sit on the noun impression, which traces back through French impression to Latin impressiōnem, from imprimō, to press into. Something pressed into a surface leaves a mark; that mark became the mark a thing leaves on your eye or your mind, and an impressionist is someone who works with that mark rather than with the thing itself.
兩個意思都站在 impression 上面。這條線經過法文 impression，回到拉丁文 impressiōnem，來自 imprimō，意思是「壓進去」。壓進去會留下痕跡。那個痕跡後來變成「一樣東西在眼睛或心裡留下的印象」。impressionist 處理的就是那個印象，而不是東西本身。
Wiktionary etymology tree in this packet (source_ref kaikki:3f6f69a190036ae4:1244941687:17117): impressionist ← impression ← French impression ← Latin impressiōnem ← imprimō ← premō.
登入就可以看每一支怎麼連回核心畫面。