glottis

n. space between the vocal chords at the upper end of the windpipe (Anatomy)

The space between the vocal cords is called the glottis.
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Glottis /glot·tis/ pl. glot´tides [Gr.] the vocal apparatus of the larynx, consisting of the true vocal cords and the opening between them. [more]Glottis - Community and Resources

Noun
1. the vocal apparatus of the larynx; the true vocal folds and the space between them where the voice tone is generated
(hypernym) speech organ, vocal organ
(part-holonym) larynx, voice box
(part-meronym) rima glottidis, rima vocalis, true glottis, glottis vera

n. glottis, space between the vocal chords at the upper end of the windpipe (Anatomy)