"Put out at interest" is a compound verb that generally means "to lend money to someone else, for which a fee or interest is charged." There are several synonyms for this phrase that can be used interchangeably, including "loan out," "invest," "deposit," "advance," and "place on loan." Other synonyms include "allocate," "position," "stake," and "commit." Each of these words carries slightly different connotations and may be used in specific contexts, so it's important to choose the right synonym for the situation. Overall, these synonyms all describe the act of lending or investing money to generate income and get a return on investments.