Possible transition between charge density wave and Weyl semimetal phase in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi mathvariant="normal">Y</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>Ir</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>7</mml:mn></mml:msub></mml:mrow></mml:math>

The subtle interplay of band topology and symmetry broken phase, induced by electron correlations, has immense contemporary relevance potentially offers novel physical insights. Here, we demonstrate charge density wave (CDW) in bulk Y$_2$Ir$_2$O$_7$ for T < 10 K, its transition to the Weyl semimetal (WSM) phase at higher temperatures. CDW is evidenced a) current nonlinear conductivity with negative differential resistance low temperature, b) frequency Debye like dielectric relaxation temperature a large constant, c) an anomaly dependence thermal expansion coefficient. WSM confirmed DC AC transport measurements which show inductive response frequencies. More interestingly, that reducing crystallite size, can be eliminated leading restoration phase.