That would be the word of knowledge, but prophesy in Acts was Holy Spirit moving upon someone to speak for edification, exhortation, but not to give forth inspired as He did with the Prophets of OT.
That's specifically not what the word or its cognates mean, plain and simple. By the time of the NT the word
prophetes means one who has supernatural knowledge. That's it. I don't use the word "inspired" because it has such a slippery meaning. Further, the word
prophetes doesn't have to mean divine authority, as evidenced below (The Talmud references are in Hebrew-Aramaic, obviously, but they show the overlap of concept):
*a philosopher is called a
prophet of immortal nature (Dio Chrysostom).
* In the Babylonian Talmud (b.Sot. 13a) Rebekah prophecies as prediction, not authority.
*Miriam (b. Meg. 14a) does the same. As does Hannah (same reference).
*Josephus says John Hyrcanus is a
prophetes, not because he had divine authority, but because he predicted the future (
Ant. 13.299-300 and
Wars 1.68-69).
*Philo refers to dreams as prophecies (
Spec Leg 1.219).
*Paul quotes Epimenides who quoted "a prophet of their own," and that pagan certainly didn't speak with the authority of God!
*The High Priest's assistants slapped Jesus and said "prophesy," to which Jesus and they clearly meant "give knowledge beyond the sense-perception."
*The woman at the well said Jesus was a prophet because she recognized he had knowledge beyond sense-perception.
All of this clearly refutes the idea that prophet just means exhorter.