Ask HN: Descriptive and Competitive App Name vs. Abstract and Uncompetitive Name

I'm stuck between 2 app names. Lifetime and Delphi: My app counts down the remaining life a person has, and includes a long-term todo list that maps events to age + weeks in a life calendar. Lifetime is extremely competitive in search, and I'm possibly ranked 50 or more on keyword "lifetime". Delphi is somewhat abstract, and it stems for Oracle of Delphi which I'm not sure many people will make the connection. The upside is that I can be ranked within the top 10 in the search ranks for "Delphi". Is relevance in search more important than search rank or the other way around?