"Weeds out" is a commonly used expression that means to remove or eliminate undesirable elements within a group or system. There are several synonyms for this phrase, such as "culls," "sorts," "screens," "evaluates," "discriminates," "purges," "prunes," "filter," or "scrutinizes". Each of these words suggests a different nuance to the process of selection and elimination. For example, culling implies isolation and removal of the weakest or sickest, whereas scrutinizing suggests a more thorough examination or investigation of what needs to be eliminated. Whatever the synonym used, the meaning remains the same, which is to eliminate unwanted, irrelevant or inefficient things or people to improve the overall performance of the system or the group.