One way to hold this word: several separate, simpler things go in, and one new thing comes out — a thing that was not lying around anywhere before. Nobody went out and collected it. It was built. Whether the pieces are chemicals on a bench, articles on a desk, or electronic tones in a machine, the move is the same: put the simple parts together until they become one whole with a character of its own.
From the word’s history
Wiktionary in the packet records it as synthesis + -ize, first attested in 1830, so the word literally names the act of carrying out a synthesis — a putting-together.
手上的資料記載這個字是 synthesis（合成、綜合）加上動詞字尾 -ize，最早見於 1830 年。字面上就是「去做一次 synthesis」，也就是「把東西合起來」這個動作本身。
Wiktionary entry supplied in this packet (source_ref kaikki:3f6f69a190036ae4:896888051:15743): From synthesis + -ize. First attested in 1830.
登入就可以看每一支怎麼連回核心畫面。