Why doesn't Commonwealth law routinely use Acceptee, like Offeror?

Question

The Oxford English Dictionary recognizes acceptee. As the jurisprudes here know, Acceptee differs from Offeror, because offers don't have to be accepted. If you want to distinguish an accepted (from an unaccepted) offer, indubitably you must use Acceptee and Acceptor! But BAILII resulted just 3 cases, and AustLII just 29 documents, for Acceptee. Why's Acceptee spurned, but not Offeror?

Cited in Akinola v Oyadare & Anor [2020] EWHC 2038 (Ch) (30 July 2020), Chitty on Contracts doesn't mention acceptee, but it mentions acceptor alongside offeree.

190. That basic law is explained in Chitty on Contracts 33rd ed as consolidated with its 1st Supplement at paragraphs 2-001 to 2-003 as follows:

"2-001

The first requirement for the formation of a contract is that the parties should have reached agreement. Generally speaking, the law regards an agreement as having been reached when an offer made by one of the parties (the offeror) is accepted by the other to whom the offer is addressed (the offeree or acceptor).

Answer 1

A good and thorough answer by ohwilleke, but I suspect the answer is a bit simpler.

We use offeror/offeree because those are useful terms. An offeror has rights and obligations distinct from the offeree's. For instance, the offeror generally has the right to modify or withdraw his offer, and the offeree has the right to bind the offeror by accepting. By using those labels, we help readers understand the parties' history and legal rights.

Once an offeree accepts the offer, he becomes an acceptor, but what else does that label tell us about him? Not too much, because his rights and obligations are essentially identical to those of the acceptee: each has a duty to perform and a right to the other's performance.

At that point, we would typically just refer to each as a party to the contract, a label that acknowledges their equal legal footing.

Answer 2

"Acceptee" Is Often Ambiguous

The Offeror and Offeree construction, like Lessor and Lessee, always comes in a pair. An act and a response to the act. But, following that logic, the "Acceptor" should be the person who accepts an offer to enter into a contract, and an acceptee should be the person who made the offer, since they receive the acceptance.

According to the OED at the link in the OP, the word "Acceptee" has two senses which mean basically opposite things.

One sense is synonymous with Acceptor in the quoted language in the OP, and is the person who accepts an offer, but it is confusing because the construction is not parallel to Acceptor.

The second sense in the OED is one in which Acceptor is an entity that admits someone to membership (e.g. a college) and Acceptee is the person who is admitted to membership (e.g. a prospective student who decides to attend a college). But this sense isn't naturally applicable to contracts and involves something that isn't litigated.

So, the meaning of the word "Acceptee" is often ambiguous in the context of offers and acceptances of proposals to enter into contracts.

Early Uses Of Terminology Become Entrenched In Common Law Systems

Beyond this, there isn't any profound reason.

Neither "Acceptee", nor any of the other words in question (like Offeror, Offeree, and Acceptor), are used with any regularity in statutes.

All of these terms are used principally in the context of case law interpretations of common law contract rights.

Common law terminology is prone to strong "founder effects". Once a term is used once, subsequent courts citing past precedents like to quote exactly from previous court rulings.

Often, there is more than one word which would be appropriate to describe a participant in a contract formation process, as you point out, but a court will generally use only one in any given court opinion for clarity's sake. Calling the same person an Offeree in one paragraph of a court opinion, and an Acceptee in another, would frequently be confusing.

In part for the substantive reasons, but also just as a matter of random happenstance, "Offeree" came to be used in some of the early opinions rather than Acceptee, and everyone writing court opinions and making legal arguments who followed tended to imitate that early word choice so as to invoke the legal authority of the early precedents.

So, one term "went viral" in the common law opinions that cited the early decisions, and another one which would have been equally suitable fell into disuse in legal writing.