1.
thing; article; piece of goods
Refers to an item or thing, often with a judgmental or evaluative nuance. Frequently used in negative or critical contexts to describe something of questionable quality or character.
とんでもない代物だ。
It's an outrageous piece of work.
Almost always carries an evaluative tone — the speaker is passing judgment on the quality or nature of the item. Most commonly used in negative contexts (ひどい代物, とんでもない代物), but can also express impressed surprise (なかなかの代物).
Not interchangeable with neutral words like 物 or 品物, which lack this judgmental nuance.