17 across
Rat
traps
however
ending
in
pipe
where
current
flows
(7)
Rat traps however ending in pipe where current flows (7)
hints
0
checks
0
hints
The definition is at the end of the clue.
How the clue works
The definition is where current flows, giving CATHODE. The wordplay builds up in two parts. First, CAD ("rat") traps THO (an archaic form of "however"), giving C-A-THO-D — that is, THO inside CAD. Then we add E, the last letter ("ending in") of "pipe". Put it all together: CATHOD + E = CATHODE.