An option (lookback option) that is only exercisable by its holder at expiration date (expiry date). It allows the holder to purchase (if a call) or sell (if a put) some underlying asset at expiration at the minimum price (if a call) or maximum price (if a put) during the lifespan of the option.

Lookback options, whether European or not, are path-dependent options whereby the trader can evaluate the possibility of the maximum/ minimum price of the underlying asset.