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by¹

(bī)

prep.

1. Close to; next to: the window by the door.

2. With the use or help of; through: We came by the back road.

3. Up to and beyond; past: We drove by the house.

4. At or to: stopped by the bakery; came by the house.

5. In the period of; during: sleeping by day.

6. Not later than: by 5:30 PM.

a. In the amount of: letters by the thousands.

b. To the extent of: shorter by two inches.

a. According to: played by the rules.

b. With respect to: siblings by blood.

9. In the name of: swore by the Bible to tell the truth.

10. Through the agency or action of: was killed by a bullet.

11. Used to indicate a succession of specified individuals, groups, or quantities: One by one they left. They were persuaded little by little.

12.

a. Used in multiplication and division: Multiply 4 by 6 to get 24.

b. Used with measurements: a room 12 by 18 feet.

c. Toward. Used to express direction with points of the compass: south by east.

adv.

1. On hand; nearby: Stand by.

2. Aside; away: We put it by for later.

3. Up to, alongside, and past: The car raced by.

4. At or to one's home or current location: Stop by later today.

5. Into the past: as years go by.

Idiom:

by oneself

1. Without company; alone: went by herself.

2. Without help: wrote the book by myself.

[Middle English bi, be, from Old English bī, be; see ambhi in the Appendix of Indo-European roots.]

by²

(bī)

Variant of bye¹.

by- or bye-

pref.

1. Near; at hand: bystander.

2. Out of the way; aside: bypass.

3. Secondary: byproduct.

4. Past: bygone.

abbr.

budget year

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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