Definition of horizontals:
(adj) :
Perpendicular to the vertical; parallel to the plane of the horizon; level, flat.
(adj) :
(marketing) Relating to horizontal markets
(adj) :
(sex, euphemistic) Relating to sexual intercourse.
(adj) :
(biology) Being or relating to the transmission of organisms between biotic and/or abiotic members of an ecosystem that are not in a parent-progeny relationship.
(adj) :
(music, of an interval) Having the two notes sound successively.
(adj) :
(wine) Involving wines of the same vintages but from different wineries.