Nxehtësia

Nxehtësia is the Albanian term for heat or warmth. In everyday language it denotes the sensation of hotness and the quality of being warm. In scientific contexts, nxehtësia refers to the transfer of thermal energy between bodies or systems driven by a temperature difference.

In thermodynamics, heat is energy in transit, not an intrinsic property of a body. The SI unit is the joule; heat can also be expressed in calories. For a substance of mass m and specific heat capacity c, the heat transferred during a temperature change is Q = m c ΔT. During a phase change, Q = m L, where L is the latent heat.

Heat transfer occurs mainly by conduction, convection, and radiation. Conduction transfers energy through contact, convection via fluid movement, and radiation through electromagnetic waves. The Zeroth Law establishes thermal equilibrium, while the First Law relates heat exchange to changes in internal energy and work.

Practically, nxehtësia is central to engineering, building design, and everyday activities such as cooking and climate control, where insulation, heating, and cooling manage heat flow. In meteorology and geology, temperature and heat distribution influence weather patterns and Earth's energy balance.

Etymology: from the Albanian adjective nxehtë (hot); the suffix -ësia forms abstract nouns such as "heat" or "warmth".