my reputaion was made (ruined) when at 13 or so, someone thru out the insult to Cathy C. "you have a head like a seive!" Cathy was aware she was being insulted, but said, "what's a seive?" and i chimed in " a colender"

now days, i tend to think of a seive as more like a strainer, and made of wire mesh-- and a colendar as a bowl with perforations.. not quite the same thing, or quite interchangable.. (i could use a seive to drain my pasta, but i wouldn't use a colender to remove lumps bits from sugur or flour..only a seive would do that. )