Q-word

[…] was derived through morphological means. This is the situation in languages in which the indefinite marker seems to have been derived from the q-word. In other languages the q-word was morphologically derived from the indefinite word.

Source: wiktionary

The q-word questions ask for information about that element only which is replaced by the question word. The position of the q-word is in situ of the element it replaces, except when replacing a subject.

Source: wiktionary

Last semester, I noticed that students in my Introduction to Queer Studies course (Queer Theory/Queer Lives) were just as interested in the b-word (bisexuality) as the q-word (queer). They perked up when I made references to the history of bisexual movements, and by the end of the semester they began to draw interesting connections between "bi" and "queer."

Source: wiktionary

Even among Western doctors and surgeons, there is a widely held superstition about the q'''-word - 'quiet' - which should never be spoken during a hospital shift.

Source: wiktionary