ごご午後gogo
1.
The period of time that begins after noon and extends to midnight, often associated with post-lunch activities.
2.
Specifically refers to the time frame from midday until evening, marked by a transition from daylight to dusk.
Example:
その急行は午後六時三十分着だ。
ごごいち午後一gogoichi
1.
The earliest scheduled activity or event occurring in the afternoon of the same day.
2.
A colloquial reference to the exact time when the afternoon begins, typically denoting the very first task or appointment.