We don't have synonyms for guardrails yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are guardrail, guard rails and guard rail.
(n) :
(Canada, US) A strengthened barrier installed on the sides of a (usually major) road to keep vehicles on the highway and reduce the risk and/or impact of crashes.
(n) :
A rail set alongside a dangerous place as a barrier, to improve safety.
(n) :
(figurative, by extension) Any barrier designed to prevent accidents or mistakes.
(n) :
(Canada, US) A strengthened barrier installed on the sides of a (usually major) road to keep vehicles on the highway and reduce the risk and/or impact of crashes.
(n) :
A rail set alongside a dangerous place as a barrier, to improve safety.
(n) :
(figurative, by extension) Any barrier designed to prevent accidents or mistakes.