Riddle

[Kaishe48]

My first is in tick but not in tock
my second is in sheep but not in shock
my third is a vowel used most of all
my fourth is in peep and also in pop
my whole was wide and also tall
and meant to be a safe place for all

(the topic is castles, defences and weapons)
any help much appreciated - thankyou

[Canary42]

If the first was "and also in" then I would go for KEEP, but I'm at a loss otherwise.

[Kaishe48]

thanks Canary42. That was my thinking too, but wondered if I'd missed some vital clue.
I think it must be a typing error.
many thanks for your help.
Kaishe48

[Headley]

Peter?

[Kaishe48]

thankyou Headley.
I'd thought of it as a 4 letter word, but maybe not!!
many thanks