cairn

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A mound of stones erected as a memorial or marker.

Century Dictionary and Cyclopedia

1. n. A heap of stones; especially, one of a class of large heaps of stones common in Great Britain, particularly in Scotland and Wales, and generally of a conical form. They are of various sizes. Some are evidently sepulchral, containing urns, stone chests, bones, etc. Some were erected to commemorate a great event, others appear to have had a religious significance, while the modern cairn is generally set up as a landmark, or to arrest the attention, as in surveying, or in leaving a record of all exploring party or the like. See barrow.

Wiktionary

1. n. A rounded or conical heap of stones erected by early inhabitants of the British Isles, apparently as a sepulchral monument.
2. n. A pile of stones heaped up as a landmark, to guide travelers on land or at sea, or to arrest attention, as in surveying, or in leaving traces of an exploring party, etc.
3. n. A cairn terrier.

GNU Webster's 1913

1. n. A rounded or conical heap of stones erected by early inhabitants of the British Isles, apparently as a sepulchral monument.
2. n. A pile of stones heaped up as a landmark, or to arrest attention, as in surveying, or in leaving traces of an exploring party, etc.

WordNet 3.0

1. n. a mound of stones piled up as a memorial or to mark a boundary or path
2. n. small rough-haired breed of terrier from Scotland