off guard; defenseless; no guard
Wasei-eigo from English 'no guard'. Used in contexts like boxing, martial arts, or metaphorically for being unprepared or vulnerable.
wasei-eigo (Japanese-coined English), from no guard
He took a punch with his guard down.
During the match, he was caught off guard for a moment and got hit.
Variant with interpunct; less common but seen in some contexts.
Wasei-eigo from English 'no guard'. The exact origin is uncertain, but it likely entered Japanese through boxing or combat sports terminology.