It's a Japanese word that has just one meaning and can only be used in one context. It can't be misunderstood as it literally means to test a new weapon,mainly katanas on any unsuspecting passerbys. This was mainly done at night and definitely caused alot of deaths. There were also rumors that mentioned how performing tsujigiri 1,000 times could heal any illness.
At one point in time it was also legal for samurais to kill any nonsamurai.
The pokemon night slash attack is also known as tsujigiri in the Japanese version.