Dictionary.net

Such as are either by word of mouth or are committed to writing, but are not under seal. The common law draws only one great line, between things under seal and not under seal. Wharton. Synonyms distinguished. The term "agreement" is often used as synonymous with "contract." Properly speaking, however, it is a wider term than "contract" (Anson, Cont. 4.) An agreement might not be a contract, because not fulfilling some requirement of the law of the place in which it is made. So, where a contract embodies a series of mutual stipulations or constituent clauses, each of these clauses might be denominated an "agreement." "Agreement" is seldom applied to specialties; "contract" is generally confined to simple contracts; and "promise" refers to the engagement of a party without reference to the reasons or considerations for it, or the duties of other parties. Pars. Cont. 6. "Agreement" is more comprehensive than "promise;" signifies a mutual contract, on consideration, between two or more parties. A statute (of frauds) which requires the agreement to be in writing includes the consideration. Wain v. Warlters, 5 East, 10. "Agreement" is not synonymous with "promise" or "undertaking," but, in its more proper and correct sense, signifies a mutual contract, on consideration, between two or more parties, and implies a consideration. Andrews v. Pontile, 24 Wend. (N. Y.) 2S5.