ostiole

A small opening or pore, as of a fruiting body.

A small opening or entrance; a little ostium.

In zoology: One of the small inhalant pores or orifices of sponges.

The exterior opening of a stomate. See stomate.

Any small orifice.

A small hole or opening through which certain fungi release their mature spores.

A similar hole or opening in plants, such as the opening of the involuted fig inflorescence through which fig wasps enter to pollinate and breed.

a small pore especially one in the reproductive bodies of certain algae and fungi through which spores pass