mild-mannered 
adjective
(Of a person) gentle and not given to extremes of emotion: karate was introduced into Japan by a mild-mannered Okinawan schoolmaster...
- And he is on BBC2 in the evenings now, asking his aggressive questions at mild-mannered members of the public.
- He sounds like a slightly demented five-year-old child, while at the same time looking like anybody's mild-mannered uncle.
- He's normally mild-mannered, easy-going and a joy to work for.
- Uniformity, Act of
- uniformly
- uniform resource locator
- unify
- unijunction
- unilateral
- Unilateral Declaration of Independence
- unilateralism
- unilateralist
- unilaterally
- unilinear
- unilinearly
- unilingual
- unilingualism
- unilingually
- unilluminated
- unillustrated
- unilocular
- uniloculate
- unimaginable
- unimaginably
- unimaginative
- unimaginatively
- unimaginativeness
- unimagined