To insert an item, usually a musical instrument, entirely into ones rectum.
Chris: you know i sosceles triangles?
Jane: I wondered why you'd been spending so much time in the music department recently.

Doctor: I'm afraid I'm gong to have to sosceles this thermometer, it might be a little uncomfortable.
Chris: that's OK, I'm used to it, I had a didgeridoo in there the other day!
by Maffsteecher June 29, 2009
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