WASHINGTON — President Trump on Thursday defended his use of the word “animals” to describe dangerous criminals trying to cross into the United States illegally, saying that he had been referring to members of the brutal transnational gang MS-13 when he used language critics called inappropriate.

“I’m referring, and you know I’m referring, to the MS-13 gangs that are coming in,” Mr. Trump told a reporter who asked him about the remark, a day after using the term during a White House meeting about immigration. “We have laws that are laughed at on immigration. So when the MS-13 comes in, when the other gang members come into our country, I refer to them as animals. And guess what — I always will.”

The president was doubling down on a statement he made on Wednesday at a round-table discussion with state and local officials from California, at which Mr. Trump and his guests criticized the state’s so-called sanctuary laws, which restrict communication between local law enforcement and federal immigration officers. He used the word as one of the officials argued that the state laws made it more difficult for her to share information with immigration authorities about dangerous criminals, including MS-13 members.

“We have people coming into the country, or trying to come in — we’re stopping a lot of them,” Mr. Trump said in response, during a session where he complained that the United States has “the dumbest laws on immigration in the world.”