Fastener?
Teat
Glad you flushed !
Looks a bit like a bowel examination.
Nozzle
Does heat come out of it ?
Good shoutThermos flask ?
Thermos flask ?
Bottle top
Is it a part of a vacuum cleaner?
The bottom of a salt/pepper pot?
It is used to connect it to something, but not a fastener that you would normally think of.Lift the dot fastener?
Clip on a duvet cover
Light holder / socket?
No.Is it the earpiece of headphones?