touch·wood 
(tŭchwd′)
(tŭchwd′)n.
Material, such as decayed wood, that is used as tinder; punk.
[From its being easy to ignite.]
- inseminate
- insemination
- inseminator
- insensate
- insensately
- insensateness
- insensibility
- insensible
- insensibleness
- insensibly
- insensitive
- insensitively
- insensitiveness
- insensitivity
- insentience
- insentient
- inseparability
- inseparable
- inseparableness
- inseparably
- in series
- insert
- inserter
- insertion
- insertional