Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
indictĭo, ōnis, f. [2. indico], a declaration (post-Aug.). 
- I.  In gen.: belli, Flor. 4, 10, 2; Paul. ex Fest. p. 254, 34.
 
- II.  In partic. 
 
- A.  A declaration or imposition of a tax; an impost, tax, Plin. Pan. 29; Dig. 33, 2, 28.
 
- B.  A space of fifteen years, Cod.Th. 11, 28, 3: SECVNDA, Inscr. Orell. 1160.