题主

題主
tízhǔ
  1. (Internet) one who asks a question on a Q&A site; original poster (OP); questioner
  2. one who asks a question on a Q&A site; original poster (OP); questioner

Wiktionary

Entry Composition

=1 题 Tí surname Ti
=1 题 tí
  1. topic
  2. problem for discussion
  3. exam question
  4. subject
  5. to inscribe
  6. to mention

classifiers: 個, 道
=2 主 zhǔ
  1. owner
  2. master
  3. host
  4. individual or party concerned
  5. God
  6. Lord
  7. main
  8. to indicate or signify
  9. trump card (in card games)
=2 主 zhù
  1. Classifier for events.
  2. alternative form of 注 (zhù, “to pour into”)