"Θ”. This was one of the “words” used in the patent I was applying for. After looking it up, I found that this symbol stood for “Voiceless Dental Non-Sibilant Fricative”. Glad that’s cleared up.
Use it in a sentence, you ask? Certainly:
“In a preferred embodiment, the relative rotation between the first panel 300 and the second panel 500 define a relative angle, θ, between the two panels. As shown in Figures 3B-3D, θ is substantially equivalent to 180 degrees.”
It’s at this point, when in conversation with a patent lawyer, that one should simply feign understanding. “Ah, got it.”
I however, in my infinite wisdom, wanted to fully understand the patent that I was applying for and diligently asked for much clarification (and many changes). Hindsight pro tip: When paying a patent lawyer’s astronomical hourly wages, don’t diligently ask for much clarification (and many changes). I feel like cartoon butterflies now fly out of my wallet as I open it.