The phrase "stood by" has several synonyms that can be used to convey a similar meaning. One alternative is "supported," which signifies providing backing or encouragement to someone in a given situation. Another option is "stood up for," which implies taking a steadfast stance in defense of someone or something. Other possible substitutes include "backed up," "stood firm," "stood with," and "stood behind," all of which suggest an unwavering commitment to a particular person, cause, or idea. Ultimately, the choice of synonym will depend on the context in which the phrase is being used and the specific connotations that the speaker or writer wishes to convey.