the word 'tardiness' is built upon the latin adjective tardus, meaning slow or delayed, which itself may trace back to a proto-indo-european root suggesting stiffness or immobility. the latin root was adopted into english, primarily through french influence, to form the adjective 'tardy'. to this base, the native english suffix '-ness', which converts adjectives into abstract nouns indicating a state or quality, was appended. thus, the literal construction 'slow-ness' perfectly captures the modern meaning of the habit or quality of being late.

Structure: tard (slow) + i (connective) + ness (noun suffix) tard (from latin tardus, meaning slow, sluggish); i (a connective vowel used in word formation); ness (from old english -nes, a noun-forming suffix denoting a state, quality, or condition).