- to make different in some particular, as size, style, course, or the like; modify: to alter a coat; to alter a will; to alter course.
- to castrate or spay.
- to change; become different or modified.
Origin of alter
Examples from the Web for unaltering
In all but the unaltering fire of friendship I could see change creeping on.The Singing Mouse Stories
Let your altar be to the 'Unknown God,' if you like—for who can give an unaltering likeness to the Power above us?Beatrice
H. Rider Haggard
It was practised for thousands of years and opposed its unaltering form to the multiplicity of legends and local beliefs.The Oriental Religions in Roman Paganism
Her face wore a settled and unaltering expression of something missed yet never to that day for one moment forgotten.Of Walks and Walking Tours
The tree waves softly all night in the unaltering lamplight, and the moonlight is killed upon its leaves.London Impressions
Word Origin and History for unaltering
late 14c., "to change (something)," from Old French alterer "change, alter," from Medieval Latin alterare "to change," from Latin alter "the other (of the two)," from PIE *al- "beyond" (see alias (adv.)) + comparative suffix -ter (cf. other). Intransitive sense "to become otherwise" first recorded 1580s. Related: Altered; altering.