What does it mean to be a hero?

When only having read three chapters of Things Fall Apart by Chinua Achebe, it was an indistinctive decision whether Okonkwo was a hero. At first, he had traits that make him a hero; he had people respecting him and looking up to him since he won a great wrestling match. Therefore he brought pride to his tribe. Even though he was a leader and he was admired by other tribesmen, he was a very insecure and cowardly person.
He would beat his wives and his children, at times, for irrational reasons. Heros aren't suppose to harm others. Instead they are to help them; which he does do, since he is supporting his family with his farm. He was insecure in many ways. When it came down to deciding whether to kill Ikemefuna or not, he didn't want to. But he did so anyways because he didn't want to look 'weak' amongst the tribe.
Okonkwo had a huge fear of others thinking he is weak, which is why he never respected his father, Unoka. Unoka was a man full of debts, but was still a happy man. Another way Okonkwo wasn't a hero, he didn't offer support to his father instead, he just left him to be. Okonkwo was ashamed of his failure.
In the end, after he was exiled, he hung himself to death. He just gave up on life because of the fact he was ashamed of his actions. After reading the novel and looking at Okonkwo's decisions, I don't think he is a hero at all. Heros stay determined and always try to find positivity in life, Okonkwo on the other hand was just a coward.