(chemistry) A process in which the rate of a reaction in a heterogeneous two-phase system is enhanced by the addition of a substance that transfers one of the reactants across the interface between the two phases.

(physics) The velocity of propagation of a pure sine wave of infinite extent and infinitesimal amplitude.

(pharmacology) A student of pharmacology; one versed in the science of pharmacology.

plural of Philadelphia lawyer

(astronomy) A function that describes the angular distribution of light reflected from a body when illuminated from a specific direction

A form of light microscopy in which small differences in refractive index of a transparent specimen are converted into amplitude (contrast) differences in the final image.

(pharmacology) A narcotic and sedative barbiturate drug used chiefly to treat epilepsy.

A feigned punch with the fist.

The latter part of the menstrual cycle, that occurs after ovulation, in which the corpus luteum secretes progesterone to prepare the endometrium for the implantation of an embryo.

(transitive) To introduce (something) little by little, either via discrete phases of increase or (by extension) by continuous gradations; to introduce in phases, or as if by phases (gradually); to begin (something) gradually.