one yen
Refers to the one-yen coin or the amount of one yen. The one-yen coin is the smallest denomination of Japanese currency.
The one-yen coin is light and often gets lost in my wallet.
Because of the consumption tax, payments in one-yen increments have increased.
throughout; the whole area
Used as a suffix or adverb to mean 'throughout an area' or 'the whole district'. Often follows a place name or area-denoting noun.
A heavy rain warning has been issued throughout the Kanto region.
I heard that this whole area used to be rice fields.
I don't have even one yen on me right now.
A heavy rain warning has been issued for the whole Kanto region.