The Everton star was outraged that the post-match medal ceremony was conducted in Spanish, despite the final being held in California.
Howard admits his use of the f-word was wrong, although he stands by his opinion.
"I would like to apologise for my language,'' the 32-year-old is quoted as saying in the Liverpool Echo.
"I am the father of young children and I certainly do not believe profanity is appropriate in public comments. I was caught up in the heat of the moment.
"In any important international match with post-game ceremonies you would hope the tournament organisers would make sure the primary language of each participating team is used so the participants can understand what is being said.
"To fail to do this is, in my opinion, disrespectful to the players. When this occurs on your home soil, it is particularly insulting.
"We, as American players, were asked to participate in a post-game ceremony at a match in Los Angeles and we are standing there trying to show good sportsmanship and yet the ceremony is going on and we are just looking at one another struggling to understand a word.
"It was, to be honest, humiliating, and I firmly believe the tournament organisers should not have put us in that position."