The transmission of heat in a fluid by the circulation of currents.
The vertical movement of heat and moisture, especially by updrafts and downdrafts in an unstable air mass. The terms convection and thunderstorm are often used interchangeably, although thunderstorms are only one form of convection. Towering cumulus clouds are visible forms of convection.
A blade or channel for directing the flow of water to the buckets in a water wheel.
Someone who guides, especially someone hired to show people around a place or an institution and offer information and explanation, or to lead them through dangerous terrain.
A grooved director for a probe or knife in surgery.
A sign that guides people; guidepost.
A spirit believed to speak through a medium.
A member of a group marching in formation who sets the pattern of movement or alignment for the rest.
A document or book that offers information or instruction; guidebook.
Any marking or object that catches the eye to provide quick reference.
to serve as a guide for someone or something; to lead or direct in a way; to conduct in a course or path.
to act as a guide.
to exert control or influence over someone or something.
to supervise the education or training of someone.
to steer or navigate, especially a ship or as a pilot.