Full Idea
Russell used the phrase 'propositional function' (adapted from Frege) to refer sometimes to predicates and sometimes to attributes.
Clarification
'Attributes' are more commonly called 'properties'
Gist of Idea
Russell uses 'propositional function' to refer to both predicates and to attributes
Source
comment on Bertrand Russell (The Philosophy of Logical Atomism [1918]) by Willard Quine - Philosophy of Logic Ch.5
Book Reference
Quine,Willard: 'Philosophy of Logic' [Prentice-Hall 1970], p.68
A Reaction
He calls Russell 'confused' on this, and he would indeed be guilty of what now looks like a classic confusion, between the properties and the predicates that express them. Only a verificationist would hold such a daft view.