underlie
Formsunderlies, underlying, underlay, underlain
- 1To serve as the basis of something or form the foundation on which it rests.
Several unspoken assumptions underlie the entire argument.
A simple principle underlies all of her teaching.
Similarunderpin
Note
The figurative step from lying beneath: what underlies an argument holds it up out of sight, much as underpin suggests. Keep the direction straight. The foundation is the subject (a doctrine underlying a theory), never the thing built on it. The participle underlying often works almost as an adjective. Emily Carr's Klee Wyck (1941) uses the past tense of a carved cedar figure: "sincerity underlay every stroke."
- 2To lie underneath or below something.
Ancient lava flows underlie much of the island.
A network of caves underlies the old city.
Oppositeoverlie
Note
The literal core of the word, built in Old English from under- and lie. Dutch onderliggen, "to lie below, lie on the bottom of," keeps the same picture. With an object it is a staple of geology: a stratum of clay underlies the surface gravel. Watch the word order. The layer below is the subject, and whatever rests on top of it is the object.
- 3To rest in a position directly beneath something above it.
The oldest deposits underlie at considerable depth.
A layer of permafrost underlies just below the surface.
Oppositeoverlie
Note
Here the verb stands alone, with no object: the oldest deposits simply underlie, deep down or just below the surface. It conjugates like lie, not lay: underlies, underlying, underlay, underlain. That past tense is spelled exactly like the separate verb underlay, which mining links to the slanting-vein sense, so only context tells a past-tense underlie from the other word.
- 4To be subject to something, or bound to answer it, as with a charge or a challenge.
Note
A meaning inherited from Old English underliċġan, "to be subject to, give way to," and still alive in German unterliegen, "to be subject to, succumb." Walter Scott uses it in Ivanhoe (1819), where the knight of Ivanhoe underlies a rival knight's challenge: he is bound to meet it. In ordinary modern prose, answer a challenge or face a charge says the same thing.
Practice
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Origin
From Middle English underlien, underliggen, from Old English underliċġan ("to underlie, be subject to, give way to"), formed from under- plus lie. It is related to Dutch onderliggen ("to lie below") and German unterliegen ("to lie under, be subject to").