from The American Heritage® Dictionary of the English Language, 4th Edition
- prep. To the inside or interior of: went into the house.
- prep. To the activity or occupation of: recent college graduates who go into banking.
- prep. To the condition, state, or form of: dishes breaking into pieces; changed into a butterfly.
- prep. So as to be in or be included in: parties entering into an agreement; wrote a new character into the play.
- prep. Informal Interested in or involved with: They are into vegetarianism.
- prep. To a point within the limits of a period of time or extent of space: well into the week.
- prep. In the direction of; toward: looked into the distance; pointed into the sky.
- prep. Against: crashed into a tree.
- prep. As a divisor of: The number 3 goes into 9 three times.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- prep. Going inside (of)
- prep. Going to a geographic region.
- prep. Against, especially with force or violence.
- prep. Producing, becoming
- prep. Of (when describing duration)
- prep. Intensely interested in or attracted to.
- prep. Taking distinct arguments to distinct values.
- prep. The operation of division, with the denominator expressed first.
- prep. Investigation of a subject.
from the GNU version of the Collaborative International Dictionary of English
- prep. To the inside of; within. It is used in a variety of applications.
- prep. Expressing entrance, or a passing from the outside of a thing to its interior parts; -- following verbs expressing motion
- prep. Expressing penetration beyond the outside or surface, or access to the inside, or contents
- prep. Indicating insertion.
- prep. Denoting inclusion.
- prep. Indicating the passing of a thing from one form, condition, or state to another
from The Century Dictionary and Cyclopedia
- In and to; to and in: implying motion: used to express any relation, as of presence, situation, inclusion, etc., that is expressed by in, accompanied by the idea of motion or direction inward. Compare in.
- Of change of condition: after such verbs as pass, fall, grow, change, convert, transmute, etc. Into, as thus indicating change, may when used with an intransitive verb give it a transitive force: as, to talk a man into submission; to reason one's self into error.
- In: not implying motion: as, he fought into the Revolution.
- Unto; until. Compare intil.
- Within, implying deficiency: as, the pole was long enough into a foot.
Old English intō, equivalent to in + to. (Wiktionary)