My surname is Mallicoat, pronounced like the first two syllables of malady followed by the ordinary word coat.

The Dictionary of American Family Names [1] has these two relevant entries:

Malicoat (250) English: unexplained. Compare MALLICOAT.

Mallicoat (240) English: unexplained. Compare MALICOAT.

It is an uncommon name. The numbers given (250 and 240) are the frequency of the surname in the "sample of 88.7 million listings in the [Dictionary of American Family Names] database." For comparison, the frequency of Newman is 39,339.

Oldtimers in my family have done some genealogical work, concluding (per my father) that Mallicoat is a "habitational name from a place so named in Devon county, England." The supposed place is the village of Mullacott, near Ilfracombe. The village appears in the Domesday Book of 1086 as Molecote.

All of the American Mallicoats are apprently descended from one John Mallicote, who was born ca. 1616–1660 in England and died ca. 1657–1740 in the Colony of Virginia.

A Jamaican cable man, when installing a modem at my apartment long ago, told me that there are Mallicoats in Jamaica, too.