Some crucial definitions and abbreviations:
 
bifolium/ bifolia                                                       hair
booklet                                                                 hair/flesh disturbance
call number                                                           incipit
catchword                                                             pagination
codex                                                                   pastedown
collation                                                                pecia
colophon                                                              quaternion
columns (and how they're referred to)                      quire
explicit                                                                 recto
flesh                                                                     scribe
flyleaf                                                                   signature
foliation                                                                stub
folio (and abbreviations of reference)                        verso