"Title Elimination" usually refers to a mobile home or "manufactured home." Mobile homes are often classified not as "real estate" because they can be moved. Mobile homes that are not real estate are issued a vehicle title by the Department of LIcensing. They are not taxed as real estate by the county auditor.
However, a party can request a DOL title be "eliminated" and the mobile become part of the real estate. This avoids the need for a person to continually renew licensing with DOL and also, allows the mobile home to be sold with the property, as opposed to separate personal property.
Here is a link to the statutes (Revised Code of Washington - RCW) on title elimination, RCW Chapter 65.20:
RCW 65.20.010 explains the purpose of the statutory scheme pretty well, you should click on it and read it.