Stirrup-shaped ear ossicle is stapes.

Explanation

### Step-by-Step Solution:

1. **Identify the Structure**: The question states that the stirrup-shaped ear ossicle is the stapes. The stapes is indeed one of the three ossicles in the middle ear, alongside the malleus and incus.

2. **Shape and Size**: The stapes is the smallest bone in the human body and is shaped like a stirrup. This unique shape allows it to effectively transmit sound vibrations.

3. **Location in the Ear**: The stapes is located in the middle ear and connects to the oval window of the inner ear. It plays a crucial role in the auditory system.

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