competition entry; submitted work
Refers to a piece of work (art, writing, design, etc.) submitted to a contest, exhibition, or open call. Often used in formal or organizational contexts.
The grand prize was selected from among the submitted works.
The deadline for competition entries is next Friday.
出品 is a broader term for exhibiting or submitting items (including non-competitive contexts), while 応募作品 specifically refers to works submitted in response to a call for entries.
Compound of 応募 (application, submission) and 作品 (work, piece). The exact historical derivation is straightforward from the component meanings.