Last Trading Day - The third Friday of the expiration month. Options cease trading at 3:00 PM Eastern Time on the last trading day.

Leg - (Verb) A risk oriented method of establishing a two-sided position. Rather than entering into a simultaneous transaction to establish the position (a spread, for example), the trader first executes one side of the position, hoping to execute the other side at a later time and a better price. The risk materializes from the fact that a better price may never be available, and a worse price must eventually be accepted.
(Noun) In an option strategy involving many kinds of options, each option type is known as a leg.

LEAPS - Long-Term Equity Anicipation Securities. Option contracts that expires 1 year or more in the future. Sometimes option contracts that expires 6 months to a year later are also known as a LEAPS.

Level II Quotes - Real time quotes provided by NASDAQ outlining the specific bid ask spread provided by each market maker. Read All About Level II Quotes Here.

Leverage - In investments, the attainment of greater percentage profit and risk potential. A call holder has leverage with respect to a stock holder-the former will have greater percentage profits and losses than the latter, for the same movement in the underlying stock. Read About How To Calculate Options Leverage.

Limit - See Trading Limit.

Limit Order - An order to buy or sell securities at a specified price (the limit).

Liquid / Liquidity - The ease at which a purchase or sale can be made without disrupting existing market prices.

Listed Option - A put or call option that is traded on a national option exchange. Listed options have fixed striking prices and expiration dates.

Long - To be long is to own something.

LookBack Options -Exotic options which allows the holder to "Look Back" at the price action of the underlying asset during expiration to decide the optimal price at which to exercise the Lookbacks Options. Read More About LookBack Options Here!