The word 'unaltered' is a compound formed within English by combining the negative prefix 'un-' with the past participle of the verb 'alter'. The core root 'alter' traces back to Latin alter, meaning "the other (of two)," which itself originates from the Proto-Indo-European root al-, meaning "beyond." The Latin verb alterare thus carried the sense of "to change into another state." The suffix '-ed' attaches to the verb stem to create a participial adjective. Therefore, the literal construction "not changed" perfectly captures the modern meaning of remaining in an original, unchanged condition.

Structure: un (not) + alter (change) + ed (adjective suffix) - un: A prefix of Germanic origin (Old English), meaning "not," used to form negatives. - alter: A root from Latin alterare, meaning "to change," from alter meaning "other." - ed: A suffix of Germanic origin (Old English), used to form adjectives from verbs or nouns, indicating a state or condition.