Claim: The wrench typically t-shaped and rests in a hole that is fixed is a spoke wrench.
Evidence: Spoke nipples are typically T-shaped in cross section, with an internal thread running part of the way through the hole that runs along the spoke nipple's principal axis. 
A spoke nipple rests in a hole drilled radially through the wheel's rim, and the nipple is threaded onto the external thread of a spoke.