Definition of "ancré"

Still more singular blazonry is found in the coat assumed by Saint Aidaus College at Birkenhead, which uses Columbia (dove-grey) a passion-cross ancré gules : on a chief sable a ducal coronet Or: all within a border of the last, […]

1962, Thomas Baty, Julian Franklyn, Vital Heraldry, Edinburgh : The Armorial, page 33

De Heer Kilieen Van Rensselaer was Lord of Rensselaerwyck befor 1637. […] Arms : 1st gules, a cross ancré argent : 2nd argent, a fesse embattled, voided, sable : 3d argent, three antique crosses, azure : 4th or three cheveronals sable. Motto : "Niemand Zondes." Siegneurial Coronet.

1907, Richard Henry Greene, Henry Reed Stiles, Melatiah Everett Dwight, George Austin Morrison, Hopper Striker Mott, John Reynolds Totten, Harold Minot Pitman, Charles Andrew Ditmas, Louis Effingham De Forest, Conklin Mann, Arthur S. Maynard, The New York Genealogical and Biographical Record, page 299