Unassuming
Pronunciation : Un`as*sum"ing
Part of Speech : a.
Definition : Defn: Not assuming; not bold or forward; not arrogant or presuming; humble; modest; retiring; as, an unassuming youth; unassuming manners.
Source : Webster's Unabridged Dictionary, 1913
Merriam-Webster's Everyday Language Reference Set: Includes: The Merriam-Webster Dictionary, The Merriam-Webster Thesaurus, and The Merriam-Webster Vocabulary Builder