any

American Heritage® Dictionary of the English Language, Fourth Edition

1. adj. One, some, every, or all without specification: Take any book you want. Are there any messages for me? Any child would love that. Give me any food you don't want.
2. adj. Exceeding normal limits, as in size or duration: The patient cannot endure chemotherapy for any length of time.
3. pro. Any one or more persons, things, or quantities.
4. adv. To any degree or extent; at all: didn't feel any better.

Century Dictionary and Cyclopedia

1. In the singular, one, a or an, some; in the plural, some: indeterminately distributed, implying unlimited choice as to the particular unit, number, or quantity, and hence subordinately as to quality, whichever, of whatever quantity or kind; an indeterminate unit or number of units out of many or all. The indeterminate sense grows out of its use in interrogative and conditional sentences: as, has he any friend to speak for him? is there any proof of that? if you have any witnesses, produce them.
2. [In affirmative sentences, any, being indeterminate in application, in effect has reference to every unit of the sort mentioned, and thus may be nearly equivalent to every: as, any schoolboy would know that; any attempt to evade the law will be resisted: so in anybody, any one, anything, etc.
3. When any is preceded by a negative, expressed or implied, the two are together equivalent to an emphatic negative, ‘none at all,’ ‘not even one’: as, there has never been any doubt about that.
4. In the singular, one, some; in the plural, some: indeterminately distributed in the same uses as the adjective, and used absolutely or followed by of in partitive construction: with reference to persons, any one, anybody; in the plural, any persons.
5. [In this sense it might formerly have a possessive.
6. In any degree; to any extent; at all: especially used with comparatives, as any better, any worse, any more, any less, any sooner, any later, any longer, etc.
7. Also, in negative and interrogative sentences, used absolutely: as, it didn't rain any here; did it hurt him any?

Wiktionary

1. adv. To even the slightest extent, at all.
2. At least one; of at least one kind. One at all.
3. No matter what kind.
4. pro. Any thing(s) or person(s).

GNU Webster's 1913

1. adj. One indifferently, out of an indefinite number; one indefinitely, whosoever or whatsoever it may be.
2. adj. Some, of whatever kind, quantity, or number; as, are there any witnesses present? are there any other houses like it?
3. adv. To any extent; in any degree; at all.

WordNet 3.0

1. adv. to any degree or extent
2. adj. one or some or every or all without specification