H. P. Grice, "Oxford"

implicaturum: in his Oxford seminars. Grice: “I distinguish between the ‘implicatum’ and the ‘implicaturum.’” “The ‘implicatum’ corresponds to Moore’s entailment.” “For the ‘pragmatic-type’ of thing, one should use ‘implicaturum.’” “The –aturum’ form is what at Clifton I learned as the future, and a ‘future’ twist it has, since it refers to the future.” “ ‘Implicaturum esse’ is, strictly, the infinitivum futurum, made out of the ‘esse’ plus the ‘indicaturum.’ We loved these things at Clifton!”