What is Bond?

Legal Definition
In finance, a bond is an instrument of indebtedness of the bond issuer to the holders. The most common types of bonds include municipal bonds and corporate bonds. It is a debt security, under which the issuer owes the holders a debt and, depending on the terms of the bond, is obliged to pay them interest (the coupon) and/or to repay the principal at a later date, termed the maturity date. Interest is usually payable at fixed intervals (semiannual, annual, sometimes monthly). Very often the bond is negotiable, that is, the ownership of the instrument can be transferred in the secondary market. This means that once the transfer agents at the bank medallion stamp the bond, it is highly liquid on the second market.

Thus, a bond is a form of loan or IOU: the holder of the bond is the lender (creditor), the issuer of the bond is the borrower (debtor), and the coupon is the interest. Bonds provide the borrower with external funds to finance long-term investments, or, in the case of government bonds, to finance current expenditure. Certificates of deposit (CDs) or short term commercial paper are considered to be money market instruments and not bonds: the main difference is in the length of the term of the instrument.

Bonds and stocks are both securities, but the major difference between the two is that (capital) stockholders have an equity stake in the company (i.e., they are owners), whereas bondholders have a creditor stake in the company (i.e., they are lenders). Being a creditor, bondholders have priority over stockholders. This means they will be repaid in advance of stockholders, but will rank behind secured creditors in the event of bankruptcy. Another difference is that bonds usually have a defined term, or maturity, after which the bond is redeemed, whereas stocks are typically outstanding indefinitely. An exception is an irredeemable bond, such as a consol, which is a perpetuity, that is, a bond with no maturity.
-- Wikipedia
Legal Definition
In general, an obligation. More specifically:

1. In commercial law, a borrower's obligation to pay a stated amount of money after a stated amount of time.

2. In criminal law, an obligation to pay the court if a defendant fails to meet the terms of conditional release from custody. See Bail bond.
Legal Definition
Contract. An obligation or bond is a deed whereby the obligor, obliges himself, his heirs, executors and administrators, to pay a certain sum of money to another at a day appointed. But see 2 Shepl. 185. If this be all, the bond is called a single one, simplex obligatio; but there is generally a condition added, that if the obligor pays a smaller sum, or does, or omits to do some particular act, the obligation shall be void. 2 Bl. Com. 840. The word bond ex vi termini imports a sealed instrument. 2 S. & R. 502; 1 Bald. R. 129; 2 Porter, R. 19; 1 Blackf. R. 241; Harp. R. 434; 6 Verm. R. 40. See Condition; Interest of money; Penalty. It is proposed to consider: 1. The form of a bond, namely, the words by which it may be made, and the ceremonies required. 2. The condition. 3. The performance or discharge.

2.-I. 1. There must be parties to a bond, an obligor and obligee : for where a bond was made with condition that the obligor should pay twenty pounds to such person or persons; as E. H. should, by her last will and testament in writing, name and appoint the same to be paid, and E. H. did not appoint any person to, whom the same should be paid, it was held that the money was not payable to the executors of E. H. Hob. 9. No particular form of words are essential to create an obligation, but any words which declare the intention of the parties, and denote that one is bound to the other, will be sufficient, provided the ceremonies mentioned below have been observed. Shep. Touch. 367-8; Bac. Abr. Obligations, B; Com. Dig. Obligations, B 1.

3. - 2. It must be in writing, on paper or parchment, and if it be made on other materials it is void. Bac. Abr. Obligations, A.

4. - 3. It must be sealed, though it is not necessary that it should be mentioned in the writing that it is sealed. As to what is a sufficient sealing, see the above case, and the word Seal.

5. - 4. It must be delivered by the party whose bond it is, to the other. Bac. Abr. Obligations, C. But the delivery and acceptance may be by attorney. The date is not considered of the substance of a deed, and therefore a bond which either has no date or an impossible one is still good, provided the real day of its being dated or given, that is, delivered, can be proved. 2 Bl. Com. 304; Com. Dig. Fait, B 3; 3 Call, 309. See Date.

6. - II. The condition is either for the payment of money, or for the performance of something else. In the latter case, if the condition be against some rule of law merely, positively impossible at the time of making it, uncertain or insensible, the condition alone is void, and the bond shall stand single and unconditional; for it is the folly of the obligor to enter into such an obligation, from which he can never be released. If it be to do a thing malum in se, the obligation itself is void, the whole contract being unlawful. 2 Bl. Com. 340; Bac. Abr. Conditions, K, L; Com. Dig. Conditions, D 1, D 2, D 3, D 7, D 8.

7. - III. 1. When, by the condition of an obligation, the act to be done to the obligee is of its own nature transitory, as payment of money, delivery of charters, or the like, and no time is limited, it ought to be performed in convenient time. 6 Co. 31 Co. Lit. 208; Roll. Abr. 436.

8. - 2. A payment before the day is good; Co. Lit. 212, a; or before action brought. 10 Mass. 419; 11 Mass. 217.

9.-3. If the condition be to do a thing within a certain time, it may be performed the last da of the time appointed. Bac. Abr. Conditions, P 3.

10. - 4. If the condition be to do an act, without limiting any time, he who has the benefit may do it at what time he pleases. Com. Dig. Conditions, G 3.

11. - 5. When the place where the act to be performed is agreed upon, the party who is to perform it, is not obliged to seek the opposite party elsewhere; nor is he to whom it is to be performed bound to accept of the performance in another place. Roll. 445, 446 Com. Dig. Conditions, G 9 Bac. Abr. Conditions, P 4. See Performance.

12. - 6. For what amounts to a breach of a condition in a bond see Bac. Abr. Conditions, 0; Com. Dig. Conditions, M; and this Dict. tit. Breach.
-- Bouviers Law Dictionary
Legal Definition
v. To give bond for, as for duties on goods; to secure payment of duties, by giving bond. Bonded, secured by bond. Bonded goods are those for the duties on which bands are given.
-- Black's Law Dictionary
Legal Definition
n. A contract by specialty to pay a certain sum of money; being a deed or instrument under seal, by which the maker or obligor promises, and thereto binds himself, his heirs, executors, and administrators, to pay a designated sum of money to another; usually with a clause to the effect that upon performance of a certain condition (as to pay another and smaller sum) the obligation shall be void. U. S. v. Rundle, 100 Fed. 403, 40 C. C. A. 450; Turck v. Mining Co., 8 Colo. 113, 5 Pac. 838; Boyd v. Boyd, 2 Nott & McC. (S. Ct) 126.

The word "bond" shall embrace every written undertaking for the payment of money or acknowledgment of being bound for money, conditioned to be void on the performance of any duty, or the occurrence of anything therein expressed, and subscribed and delivered by the party making it, to take effect as his obligation, whether it be sealed or unsealed ; and, when a bond is required by law. an undertaking in writing without seal shall be sufficient. Rev. Code Miss. 1880, § 19.

The, word "bond" has with us a definite legal signification. It has a clause, with a sum fixed as a penalty, binding the parties to pay the same, conditioned, however, that the payment of the penalty may be avoided by the performance by some one or more of the parties of certain acts. In re Fitch, 3 Redf. Sur. (N. Y.) 459.

Bonds are either single (simple) or double, (conditional.) A single bond is one in which the obligor binds himself, his heirs, etc., to pay a certain sum of money to another person at a specified day. A double (or conditional) bond is one to which a condition is added that if the obligor does or forbears from doing some act the obligation shall be void. Formerly such a condition was sometimes contained in a separate instrument, and was then called a "defeasance."

The term is also used to denote debentures or certificates of indebtedness issued by public and private corporations, governments, and municipalities, as security for the repayment of money loaned to them. Thus, "railway aid bonds" are bonds issued by municipal corporations to aid in the construction of railroads likely to benefit them, and exchanged for the company's stock. In old Scotch law. A bond-man; a slave. Skene.
See also
-- Black's Law Dictionary
Legal Definition
An instrument under seal whereby one binds himself to do or not to do a certain act; bail; a surety. See 26 L. Ed. (U. S.) 88.
-- Ballentine's Law Dictionary