Describing communication systems with a smaller bandwidth than wideband.(adjective)
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Use "narrowband" in a sentence
"My work with dye lasers made me aware of the exciting developments in narrowband dye lasers and their applications to atomic spectroscopy being done by Ted"
"But the market for dial-up services, sometimes derisively called "narrowband," continues to shrink."
"Traditional phones used with the "narrowband" PSTN (public switched telephone network) sample at a mere 8 KHz."