1. Literally, to speak with a loud enough voice that others will be able to hear one in the midst of other voices or background sounds. Everyone was shouting all at once, so I could barely make myself heard at the meeting. She tried to make herself heard above the dun of the party, but no one was listening.

2. To have one's opinion, beliefs, or desires understood, validated, or acquiesced to. Working-class voters made themselves heard very clearly this election, electing a huge number of candidates who have promised to represent their views in congress. If you try to take on the huge corporate lobbyists in this country, you had better have a truckload of cash at your disposal or you'll never make yourself heard.