watch (n.) 4
time interval, period of time
2H4 IV.v.29 [Prince Henry to himself, of King Henry IV's sleep] Yet not so sound ... / As he whose brow with homely biggen bound / Snores out the watch of night
Oth I.i.124 [Roderigo to Brabantio] At this odd-even and dull watch o'th' night
R2 V.v.52 [Richard alone] My thoughts are minutes, and with sighs they jar / Their watches on unto mine eyes