This ambiguity is why &quot;Structure and Interpretation of Computer Programs&quot; avoids the term &quot;closure&quot; when talking about free variables in a procedure.<p><a href="https:&#x2F;&#x2F;sarabander.github.io&#x2F;sicp&#x2F;html&#x2F;2_002e2.xhtml#FOOT72" rel="nofollow">https:&#x2F;&#x2F;sarabander.github.io&#x2F;sicp&#x2F;html&#x2F;2_002e2.xhtml#FOOT72</a>