maybe not a suitable doubt at MTECH level... anyhow
The symbol L for inductance was chosen to honor Heinrich Lenz (1804-1865), whose pioneering work in electromagnetic induction was instrumental in the development of the final theory. If you recall, Lenz' law states that the induced current in a circuit always acts in a manner that opposes the change that created it in the first place. This observation is why there's a minus sign in all the different versions of Faraday's law. Lenz' gave us the minus sign and we honor him with the symbol L.