First time being in an applied math lab - what are some tips to overcome shyness? This will be my first semester in an applied math lab.  After spending a couple of years taking all theoretical math courses, essentially working in isolation the entire time, and finishing a thesis, essentially only interacting in person with my advisor, I will now be part of a group doing some experimental work for a semester.  We are expected to write journal-style papers (not too long, less than 10 pages), following a journal of the professor's choice.

I found this setting to be extremely uncomfortable.  I felt that I was the only one who had to ask things such as, "what is viscosity?."

What are some tips to overcome this feeling of holding myself back from having an active dialogue with my lab professor?  How did you guys do it, when you first started at a lab?  I feel utterly inept with interacting in a group setting.

The professor is super cool and very informal and speaks very intuitively, so as not to scare off the first-timers, I think.
Since you are asking about viscosity, there must be some kind of fluid dynamics in your lab. Schaum's Outline of Fluid Dynamics is quite useful as it has worked out problems.

If you have actively avoided all social situations, never asked a question in class, or even had lunch with a fellow student, then perhaps you need to investigate resources at your institution to help overcome your extreme shyness. This will be a significant problem for you in the future - regardless of whether you stay in academia - if you don't take care of it now. Don't wait until you get older.