What is the oldest common English word?

I'm trying to formalize What is the oldest still-in-use English word? which was closed as vague.

Consider the "age" of a word to be the length of time since it was first used with the (more-or-less) the current meaning and pronunciation.

Obviously, there are lots of words date from Classical Antiquity: Coitus, agenda, and terminus are among thousands of words that would mean the same to Julius Caesar as they do to us.
[Assignment for the under-worked: write a logical, grammatical English sentence consisting entirely of such words; extra credit if it also makes sense in Latin.]

There are even words preserved untouched from ancient Greece (echo, academe, halcyon, stasis).

Are there any word that pre-dates those, such as some word that a Mycenaean potter or a Hittite horseman would say that, I don't know, Matt Lauer would understand perfectly?

My guess is ma, meaning mother, but I have no proof.

One candidate would be the Hittite word for "water", which was "watar" or "wadar" (there are different views on exactly what the consonant was).

According to a press release from Reading University, "I", "we", "one", "two" and "three" are among the oldest.

Based on computer models of Indo-European language evolution, they estimate these words to be at least 10,000 years old and possibly as much as 30,000 years.