Philologists (linguists) distinguish between different clipped forms- those which have lost the rear parts of the original ; and aphetic forms, those which have lost their front.

For example, fan is a clipped form of fanatic, pike an aphetic form of turnpike. But the terms clipping and clipped form are also used generically for the cutting off of either end of the original word.

Technically, they are abbreviations which began as slang (deli from delicatessen, and psych, math, soc, and chem on nearly every college campus), but lasting clipped forms frequently become Informal (flu, from influenza) or even Standard (bus, from omnibus).

Is it something that people do deliberately ?