Unit .
You tell me :P
ache
Butt is four letters! It's short for buttocks.
Twix
Starts with a
john Another answer: While "John" is a name, there is no word that ends in "hn" with only four letters.
It is known as a kepi.
Iran and Oman are countries. They end with the letters an.
tofu
Four letter words using those letters and ending in 'l' are:haulhealteal
A slip or a ramp is where a boat berths.
faro