thenabouts
Denoting a general time period (i.e. Sunday, Monday, Tuesday) centered around a specific point in time (i.e. Monday).  The surrounding time is thus linked to the specific point and is considered in the same "bracket" of time.  Similar to the word "thereabouts" as it denotes a general location of a place in space, thenabouts is used to estimate or give a general location of a place in time and can be used to denote a specific time of day or a group of days, generally one on either side of the specified day.
Example:

(Hour)

Franz:  When are you getting back to Santa Barbara?
Esmerelda:  Well I'm probably going to take the trip slowly, so I'd imagine seven o'clock or thenabouts.

(Day)

Franz:  When are you getting back to Santa Barbara?
Esmerelda:  Saturday, so I'll see you Sunday or thenabouts.