fingertip
noun /ˈfɪŋɡətɪp/
  /ˈfɪŋɡərtɪp/
 [usually plural]Idioms - the end of the finger that is furthest from the hand指尖 - Apply the cream gently using your fingertips.用指尖轻轻涂抹面霜。 
 Collocations DictionaryFingertip is used before these nouns:- search
 
- Apply the cream gently using your fingertips.
Idioms 
have something at your fingertips 
- to have the information, knowledge, etc. that is needed in a particular situation and be able to find it easily and use it quickly掌握(信息等);熟悉,精通(知识等);对…了如指掌;有…随时可供使用 - I made sure I had all the facts at my fingertips before attending the meeting.在参加会议之前,我确保掌握了所有的事实。 
 
- I made sure I had all the facts at my fingertips before attending the meeting.
to your fingertips 
- (British English) in every way完全;十足 - She's a perfectionist to her fingertips.她是个道道地地的完美主义者。 
 
- She's a perfectionist to her fingertips.