fill-in

Short definition from Wiktionary

Noun

1. 1
   A temporary replacement for another, especially at a job.
2. 2
   A substitution.
3. 3
   An intermediate result that must be stored temporarily during the course of a sparse matrix computation.
4. 4
   A question or puzzle in which one is expected to fill in a missing part of something.
5. 5
   A musical embellishment (usually percussion) that is added to connect musical phrases.
6. 6
   Something added to fill a gap.
7. 7
   Something added to increase the size of something; padding or filler.
8. 8
   A product category that is used to complete a range or variety of a product line.

Verb

1. 1
   To fill; to replace material that is absent or has been removed.
2. 2
   To inform somebody, especially to supply someone missing or missed information.
3. 3
   To substitute for somebody or something.
4. 4
   To complete a form or questionnaire with requested information.
5. 5
   To beat up; to physically assault.