From the NY Times:
Justices Turning More Frequently to Dictionary, and Not Just for Big Words
By ADAM LIPTAK

WASHINGTON — In a decision last week in a patent case, Chief Justice John G. Roberts Jr. puzzled out the meaning of a federal law by consulting the usual legal materials — and five dictionaries.

One of the words he looked up was “of.” He learned that it means pretty much what you think it means.

In May alone, the justices cited dictionaries in eight cases to determine what legislators had meant when they used words like “prevent,” “delay” and “report.” Over the years, justices have looked up both perfectly ordinary words (“now,” “also,” “any,” “if”) and ones you might think they would know better than the next guy (“attorney,” “common law”).

All of this is, lexicographers say, sort of strange.

“I think that it’s probably wrong, in almost all situations, to use a dictionary in the courtroom,” said Jesse Sheidlower, the editor at large of the Oxford English Dictionary. “Dictionary definitions are written with a lot of things in mind, but rigorously circumscribing the exact meanings and connotations of terms is not usually one of them.”

And in a very quick, just for fun (?) search:

Carcieri v. Salazar: “At that time, the primary definition of “now” was “[a]t the present time; at this moment; at the time of speaking.” Webster’s New International Dictionary 1671 (2d ed.1934); see also Black’s Law Dictionary 1262 (3d ed.1933) (defining “now” to mean “[a]t this time, or at the present moment” and noting that “ ‘[n]ow’ as used in a statute ordinarily refers to the date of its taking effect …” (emphasis added)).”

Nevada v. Hicks: “(“Process” is defined as “any means used by a court to acquire or exercise its jurisdiction over a person or over specific property,” Black’s Law Dictionary 1084 (5th ed.1979), and is equated in criminal cases with a warrant, id., at 1085.)”

U.S. v. Lara (J. Thomas, concurring): “The sovereign is, by definition, the entity “in which independent **1644 and supreme authority is vested.” Black’s Law Dictionary 1395 (6th ed.1990). It is quite arguably the essence of sovereignty not to exist merely at the whim of an external government.”

Minnesota v. Mille Lacs Band (C.J. Rehnquist, dissenting):”Usufructuary rights are “a real right of limited duration on the property of another.” See Black’s Law Dictionary 1544 (6th ed.1990).”

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