Thorny, as a plant. Covered with or having sharp, pointed projections. See examples of spiny used in a sentence. Definition of spiny adjective in oxford advanced learners dictionary. The meaning of spiny is abounding with difficulties, obstacles, or annoyances : “ spiny ”, in webster’s revised unabridged dictionary, springfield, mass. : Covered with or having sharp-pointed processes, as an animal. Resembling a spine; Abounding in or having spines; Covered with spines (= long, sharp…. Merriam, 1913, →oclc. Thorny , as a plant. A spiny problem. Difficult to handle; Covered with spines (= long, sharp points like needles) 2. How to use spiny in a sentence. · archaic form of spinney. Spiny - meaning, definition & english examples spiny /ˈspaɪni/ /ˈspaɪni/ definition: Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.