Difficile est longum subito deponere amorem - It is difficult suddenly to put aside a long-standing love (C. Valerius Catullus)
Difficile est satiram non scribere - It is difficult not to write satire (Juevenal)
Difficile est tenere quae acceperis nisi exerceas - It is difficult to retain what you may have learned unless you should practice it (Pliny the Elder)
Difficiles nugae - Difficult trifles (Work that has little return on investment)
Digitus dei est hic - God's finger is in this
Dignitatis humanae - Human dignity
Dii lanatos pedes habent - The gods have feet of wool (Petronius, Satyricon 44 - The gods are slow to act)
Diis aliter visum - The gods see it differently
Diis manibus - Sacred to the Manes (It is a dedication whose initials abound in pagan graves - abbreviated as D.M.)
Diis manibus Sacrum - Dedicated to the Names gods (It is a dedication whose initials abound in pagan graves - Abbreviated as D.M.S.)
Dimidium animae meae - Half of my soul (Philosophical term)
Dimidium facti qui coepit habet - Half is done when the beginning is done (Horace)
Dira necessitas - Cruel necessity (Horace)
Directe ni indirecte - Directly unless indirectly (One way or the other)
Disce aut discede - Learn or leave (Motto of schools in medieval times)
Disce quasi semper victorus, vive quasi cras moriturus - Learn as though you will live forever, Live as though you will die tomorrow
Discite iustitiam, moniti, et non temnere divos - Having been warned, study justice and learn not to despise the gods (Virgil - Aeneid VI, 620)
Disertissime Romuli nepotum - Most eloquent of the descendants of Romulus (Valerius Catullus, dedicated to Cicero)
Dispositio a non domino - Disposition from the non-owner (Legal term - Disposition of property granted by a party who has no title)
Dissertatio de Arte Combinatoria - Dissertation on the combinatorial art (Book by Gottfried Leibniz)
Dissertatio de Casibus Perplexis - Dissertation on the perplexing cases (in law)
Ditat Deus - God enriches (Motto of the State of Arizona)
Dives in misericordia - On the Mercy of God (Encyclical letter written by Pope John Paul II)
Dives toletana - Toledean Godess (Motto of Cathedral of Toledo, Spain)
Divide et impera - Divide and Conquer (Julius Caesar)