A surname from Irish, anglicized from Ó Riaghain, Ó Riain (“descendant of Riaghan, Rían”). Riaghan/Rían is perhaps from rí (“king”) + -án (diminutive suffix), meaning “little king”.

plural of Ryan

A female given name, a less common spelling of Ryan.

(biochemistry, physiology) A poisonous alkaloid which occurs in the stems of the tropical American shrub Ryania speciosa (family Flacourtiaceae) and has been used as an insecticide and in experimental studies of calcium release within cells.

plural of ryanodine

Any of a class of insecticides with the same mechanism of action as the alkaloid ryanodine.

plural of ryanoid

A peptide having properties similar to that of ryanodine

(geography) A province of North Korea.