What is resonant? What is resonant? Strong and deep in tone; resounding: a resonant voice. Having a lasting presence or effect; enduring: "Cranmer compiled the first Book of Common Prayer, writing some of the most resonant phrases in the English tongue” ( Allen D. Boyer). Strongly reminiscent; evocative: a monument that is resonant of the nation's past glory. Producing or exhibiting resonance: resonant frequency excitation. Resulting from or as if from resonance: resonant amplification. Linguistics A sonorant.