cold, cool
hot, steaming, warm
brief, quick
I'll just take a quick shower.

refreshing, relaxing
electric (esp. BrE)
power
en suite, private
stall (AmE), walk-in
communal, locker-room (AmE)
outdoor

grab (AmE), have (esp. BrE), take (esp. AmE)
hit (esp. AmE)
After the game, the boys hit the showers.

run
He could hear the shower running in the bathroom.

cubicle (BrE), curtain, room, stall (AmE), unit (esp. BrE)
block (esp. BrE)
The plans include changing facilities and shower blocks.

door, head, tray
He left the shower door open.

gel
cap

rain, sleet, snow
heavy, light
intermittent, occasional, odd (BrE), scattered
frequent
blustery, squally (BrE), thundery (BrE), wintry
April, spring, summer

brave
They decided to brave the showers and headed for the coast.

die out
Scattered showers will die out by late evening.

dust, meteor

send
A light exploded, sending a shower of sparks raining down.

shower of
The grinding wheel sent out a shower of sparks.

baby
bridal, wedding

have, throw
give sb
plan, plan for
attend

invitation
I got a shower invitation from Katie.

gift

shower for
a baby shower for my sister