In HolQeD v5n2p11, we learn that if a noun following Hoch is explicitly plural, it means "all", if it's singular, it means "each" or "every".

In TKW p. 33, it is used as first noun in noun-noun pair:

Hoch 'ebmey tIjon.
Capture all opportunities.

Contrast with

Hoch 'eb tIjon
Capture each/every opportunity. 

From the paq'batlh:

Hoch tuq
Hoch puq poH
loD be' je

All tribes,
All ages,
All sexes.

And

ghIq lutDaj jatlh qeylIS
latlhpu' law' pIlmoHpu' lutvam
pa'Daq tamchoH Hoch tlhInganpu'

Then Kahless tells his tale,
The tale that inspired many before them,
And every Klingon in the room falls silent.

If Hoch follows a noun, it means "all of X" as in nIn Hoch natlhlu'pu' "All the fuel has been consumed".