Look up twang in Wiktionary, the free dictionary.

Twang is an onomatopoeia originally used to describe the sound of a vibrating bow string after the arrow is released.^[1] By extension, it applies to the similar vibration produced when the string of a musical instrument is plucked, and similar sounds. The term came to be applied to a nasal vocal resonation, and was historically used to describe "a disagreeable resonance".^[1] Later, however, the term came to be more broadly associated with regional dialects, to the extent that in some locations, "a twang is a desirable commodity".^[2]

Specific uses of the term include:

• A particular sharp vibrating sound characteristic of some electric guitars.
• A high frequency singing sound especially affected by country singers. It allows for a higher vocal reach than would be possible using the standard guttural technique and can be used as an alternative to falsetto singing. Willie Nelson almost always sings with a twang voice.