An 'annihilationist' is a person that still believes in self however believes or is cognizant the self will end at death and whatever the self possesses will be lost at death.
Iti 49 provides an example of the views of 'annihilationists' who have hate rather than greed; which it contrasts with 'eternalists' who have greed rather than hate; as follows:
[Annihilationist view] How, bhikkhus, do some overreach? Now some are troubled (harāyati), ashamed (aṭṭiyati) and
disgusted (jigucchati) by this very same being and they rejoice in (the idea of)
non-being, asserting: ‘In as much as this self, good sirs, when the
body perishes at death, is annihilated and destroyed and does not
exist after death—this is peaceful, this is excellent, this is
reality!’ Thus, bhikkhus, do some overreach.
[Eternalist view] And how, bhikkhus, do some hold back? Devas and humans enjoy being, delight in being, are satisfied with being. When Dhamma is taught to them for the cessation of being, their minds do not enter into it or acquire confidence in it or settle upon it or become resolved upon it. Thus, bhikkhus, do some hold back.
AN 10.29 describes views which are 'annihilationist'. AN 10.29 says these views are closer to Nibbana because they are expected to cause dispassion, as follows:
Bhikkhus, of the speculative views held by outsiders, this is the foremost, namely: ‘I might not be and it might not be mine; I shall not be, and it will not be mine.’ For it can be expected that one who holds such a view will not be unrepelled by existence and will not be repelled by the cessation of existence.