TL;DNR: At the time of the Founding, bribery covered both giving and taking a bribe.
Two definitions of bribery from the Founding Era.
It is often hard to say exactly what a word meant "in the English language as it existed at the time of the framers." However, in this case, it's not hard. It’s easy! There are plenty of examples of people defining bribery to include both giving and receiving. I’ve picked two.
The first is Lord Mansfield, one of the most distinguished English judges of the 18th century. In 1769, he defined bribery in the case of Rex v. Vaughan, which involved an attempt to bribe a privy councilor. Mansfield’s definition was widely quoted by American judges and treatise writers well into the 20th Century:
Wherever it is a crime to take, it is a crime to give. They are reciprocal. And in many cases...the attempt is a crime.
The second definition comes Noah Webster. He defined bribery in 1828, in the first edition of his American Dictionary of the English Language.
Bribery: The act or practice of giving or taking rewards for corrupt practices; the act of paying or receiving a reward for a false judgment, or testimony, or for the performance of that which is known to be illegal, or unjust. It is applied both to him who gives, and to him who receives the compensation…
A Bonus: James Madison on the language of the Constitution
James Madison was one of the architects of the Constitution. He played a major role in drafting the Constitution and the Bill of Right, and in the campaigns to get them ratified. It is not clear that he thought the meaning of the words at the Founding would be all that useful in figuring out what the Constitution means. In Federalist 37, he discussed the role of language in deciding what the Constitution meant. He was writing to answer critics who claimed the text of the Constitution was too unclear and vague. Here is what he said:
All new laws,
though penned with the greatest technical skill,
and passed on the fullest and most mature deliberation,
are considered as more or less obscure and equivocal,
until their meaning be liquidated and ascertained by
a series of particular discussions
Madison went on to say that human language is so deeply flawed that when God uses it, even His messages are “rendered dim and doubtful by the cloudy medium through which it is communicated.”
Although Madison's prose can be hard to follow, Federalist # 37 is worth a look.