The word 'yesteryear' is a modern poetic compound, deliberately archaic in construction. It was formed in the late 19th century by combining 'yester-', an obsolete prefix meaning 'of yesterday' (as in 'yestereve' or 'yesternight'), with the common noun 'year'. The term was popularized by its use in Edward FitzGerald's 1859 translation of 'The Rubaiyat of Omar Khayyam', where the phrase "the bird of time" is "on the wing" and has "but a little way to flutter—and the bird is on the wing" is often misquoted as "the birds of yesteryear." This literary adoption cemented its meaning, evoking a past time close enough to be remembered, yet irrevocably gone, blending the immediacy of 'yesterday' with the broader span of a 'year'.

Structure: yester (of yesterday) + year (year) yester (old english, from 'geostran', meaning 'yesterday' or 'of yesterday'); year (old english, from 'gear', meaning 'year').