n. the ratio of investment costs to payoff for a project or investment; "Profitability index is a means to determine the viability of an investment."

n. a freelance detective who carries out investigations on behalf of private clients; "The retired police officer worked as a private detective."

n. a freelance detective who carries out investigations on behalf of private clients; "The retired police officer worked as a private eye."

n. a polymer of imide monomers; "Polyimides are often used to make synthetic resins."

n. the 16th letter of the Greek alphabet

n. an antiviral drug used against HIV; interrupts HIV replication by binding and blocking HIV protease; often used in combination with other drugs

n. the ratio of the circumference to the diameter of a circle; approximately equal to 3.14159265358979323846...

adj. occurring or existing between the fertilization of an ovum and its implantation in the wall of the uterus; "Preimplantation genetic diagnosis is a screening test used to determine if genetic disorders are present in embryos."