Correct spelling for the English word "pineus" is [pˈa͡ɪnɪəs], [pˈaɪnɪəs], [p_ˈaɪ_n_ɪ__ə_s] (IPA phonetic alphabet).
The word "pineus" (or "pinus" in its original Latin form) derives from the ancient Greek word "pitys". In Greek mythology, Pitys was a nymph who was transformed into a pine tree to escape the advances of Pan, the god of shepherds and flocks. The Latin word "pinus" was borrowed from Greek and specifically referred to a pine tree. Thus, "pineus" ultimately originates from the name Pitys and the association with the pine tree.