Other forms: guards, guarded, guarding
A guard watches over a place or a person to keep them safe — a security guard, a prison guard, the guard on the gate. The verb comes with it: two dogs guard the yard.
It is also the part of a machine or a tool that stops you hurting yourself, and on British railways the guard is the member of staff in charge of the train. To be on your guard is to be watchful; to catch somebody off guard is to reach them before they are ready.
1nounguardSomebody whose job is to watch a place or a person and keep them safe.
“A guard stood at each end of the corridor.”
2verbverbTo watch over somebody or something in order to keep them safe.
“Two dogs guard the yard at night.”
3nounrailThe railway worker in charge of a train.
“The guard walked the length of the train checking tickets.”
Too few real examples of this word to estimate which sense is commonest.
Guard and ward are the same word twice: one came home through French, the other stayed. Both go back to Proto-Germanic wardāną, to watch over, and French is what turned the w into gu.
Middle English
garde
English, today
guard
From Middle English garde. From Middle English garde, from early Middle French - or late Old French guarde (“a guardian, warden, keeper”) (whence modern French garde), from the verb guarder. a doublet of garda, which is from Irish -.
Etymology from Wiktionary, CC BY-SA