How to say "jack-in-the-box" in Japanese

• びっくり箱びっくりばこ
  nounThe word for the toy itself — a box with a figure that pops out to surprise you. Use it when you mean the plaything, as in a toy shop or a children's story.
• 機械仕掛けきかいじかけ
  no-adjectivePrimarily a word for a mechanism or mechanical parts, as in explaining how a device works; its jack-in-the-box use is marginal, and it is seldom the word you want for the toy itself.

For the toy itself use 「びっくり箱」; 「機械仕掛け」 is really a word for a mechanism or mechanical parts, and its jack-in-the-box sense is secondary, so it is seldom the word you want for the toy.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• びっくり箱びっくりばこjack-in-the-box
• 機械仕掛けきかいじかけmechanism