Horizons meaning : The visible horizontal line or point (in all directions) that appears to connect the Earth to the sky. The range or limit of one's knowledge, experience or interest; a boundary or threshold. The range or limit of any dimension in which one exists. A specific layer of soil or strata A cultural sub-period or level within a more encompassing time period. Any level line or surface. The point at which a computer chess algorithm stops searching for further moves.