The Collaborative International Dictionary of English v.0.48:

Impanel \Im*pan"el\, v. t. [imp. & p. p. Impaneledor
   Impanelled; p. pr. & vb. n. Impaneling or Impanelling.]
   [Pref. im- in + panel. Cf. Empanel.] [Written also
   empanel.]
   To enter in a list, or on a piece of parchment, called a
   panel; to form or enroll, as a list of jurors in a court of
   justice. --Blackstone.
   [1913 Webster]

WordNet (r) 3.0 (2006):

impanel
    v 1: enter into a list of prospective jurors [syn: empanel,
         impanel]
    2: select from a list; "empanel prospective jurors" [syn:
       empanel, impanel, panel]

Moby Thesaurus II by Grady Ward, 1.0:

66 Moby Thesaurus words for "impanel":
   book, calendar, carve, catalog, chalk, chalk up, check in,
   chronicle, cut, docket, engrave, enroll, enscroll, enter,
   enumerate, file, fill out, grave, impanel a jury, incise, index,
   inscribe, insert, inventory, itemize, jot down, keep score, list,
   log, make a memorandum, make a note, make an entry, make out,
   mark down, matriculate, minute, note, note down, panel, pigeonhole,
   place upon record, poll, post, post up, program, put down,
   put in writing, put on paper, put on tape, record,
   reduce to writing, register, schedule, score, set down, tabulate,
   take down, tally, tape, tape-record, videotape, write, write down,
   write in, write out, write up