What does sunk mean?
Sunk is the past participle of the verb sink and also functions as an adjective. In its verb-participle sense, it describes something that has moved below the surface of water, become immersed, or fallen sharply in value or degree: the boat sank, prices sank, and confidence sank. As an adjective, it is especially familiar in the phrase sunk cost, meaning money or effort that has already been spent and cannot be recovered. The expression is important in economics and personal decision-making because a past expenditure should not, by itself, determine whether another investment is worthwhile. Sunk can also evoke a deeply unhappy or disappointed emotional state, as in a sunk feeling. The word is standard in both British and American English and is recognized by its common past-participle use as well as these established adjectival uses.
The past participle of sink, used to describe downward movement, submersion, or a decline.
"The lifeboat sank rapidly after the hull was breached."
Normally appears as the participle of sink, especially with have, had, or has.
Having descended below a surface or become irretrievably lost; characteristically used in the phrase sunk cost.
"The business considered the abandoned plant a sunk cost."
The financial sense is common in economics and business; the emotional sense, meaning deeply disappointed or dejected, is also established.
A sunk cost is money already spent that cannot be recovered, so the wiser choice is often to stop investing in what is lost.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does sunk come from?
Sunk comes from Old English sincan, with the past participle sunk appearing in medieval English; the related past tense sank developed separately. The word's deeper origin is uncertain, although it belongs to a Germanic family that includes German sinken and Dutch zinken. Modern senses such as sunk cost are figurative extensions of the older idea of something having descended below a surface and becoming irretrievably lost.
Related word forms
How sunk is actually used
As a participle, sunk is used with have, be, and other auxiliary verbs. The adjective sense is especially common in business and economics, where sunk cost refers to expenditure that has already been incurred and cannot be recovered. In literary or emotional contexts, a sunk feeling conveys profound disappointment or low spirits.
Easily confused with sunk
Sunk is the standard past participle of sink, while sunken is an adjective describing something below a surface or deeply disappointed.