Falsetto and Head tone

Falsetto noun - A male singing voice with artificially high tones in an upper register.

Head tone and falsetto are semantically related. In some cases you can use "Head tone" instead a noun "Falsetto".

Head tone noun - The higher ranges of the voice in speaking or singing; the vibrations of sung notes are felt in the head.

Falsetto and head tone are semantically related. Sometimes you can replace term "Falsetto" with "Head tone", this terms are similar.