Dict-

In academic English the preferred plural of dictum is dicta. (See -a in Latin.) Although OED records dictums as also existing, it is not recommended in academic writing.

Its original meaning in Latin was simply 'something said'. In academic writing, it most often has 'the implication of a formal pronouncement claiming or carrying some authority' (OED). This sense seems to derive from OED's sense b.: In Law, An expression of opinion by a judge on a matter of law, which is not the formal resolution or determination of a court' - in other words something which a judge says in court on a matter not directly to do with the case being judged, but something on which she or he may nevertheless be quoted as an authority by lawyers.

Dict. can also be an abbreviation for Dictionary