A firm quote is a specific type of bid or offer price for a security, typically stated by a market maker, that is binding and not identified as nominal or subject to further negotiation or review.
A round lot refers to the standard quantity of securities or commodities that are traded on an exchange. For stocks, it typically means 100 shares or any number that is easily divisible by 100, while for bonds, it is generally $1,000 or $5,000 par value.
In financial markets, a trading unit refers to the standard number of shares, bonds, or other securities that is generally accepted for ordinary trading purposes on exchanges.
