That's not the angle Quine was taking. He was saying words don't have meanings. There are behaviors, and streams of words correlated with behaviors, but nothing inside a head that is a "meaning". Quine was not talking about cases where one person would point to a square and say "square", and another person would point to a triangle and say "square". He was talking about cases where two people both point to an equilateral triangle and say "equilateral triangle", but one meant "triangle with all three sides the same" and the other meant "all three angles the same". That's not a great example, but it is a short example. Or where you ask them to raise their right hand, and they both raise their right hand, but one person unknowingly has the perception of raising his left hand, and "feels" left the way others feel right. Quine argues that these are not singular examples, but that all language is undermined by indeterminacy like this.