An albatross in golf is a score of three strokes under par on a single hole. It can only happen on a par 4 or a par 5: a hole-in-one on a par 4, or holing out in two shots on a par 5.
The term albatross was introduced in Britain, and in the United States the same score is usually called a double eagle. It is one step better than an eagle (two under par) and is much rarer, while four under par on one hole is called a condor.
Source: BBC Sport: Golf scoring terms explained.
Image: Hole 14, Par 5, by PattayaPatrol, CC BY-SA 4.0, via Wikimedia Commons.
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