What is the meaning of Pinus?

A large genus of evergreen coniferous trees, mostly found in the northern hemisphere. The genus formerly included the firs, spruces, larches, and hemlocks, but is now limited to those trees which have the primary leaves of the branchlets reduced to mere scales, and the secondary ones (pine needles) acicular, and usually in fascicles of two to seven. See Pine.

Source: Webster’s Revised Unabridged Dictionary (1913), via OPTED