BT Beṣ 16a(38) :אילימא מידי דמילפת בעינן ופת לא מילפתא והא דייסא דלא מילפתא‏ : if we say we require something which can be smeared, bread cannot be smeared (on something else); but there is the d'-dish which is not smeared (on bread)?
See the entire entry for lpt vb. Dt to be smeared (??)