diff --git a/lib/scheme/base.sld b/lib/scheme/base.sld
index c8bc9855..66ba42d0 100644
--- a/lib/scheme/base.sld
+++ b/lib/scheme/base.sld
@@ -38,7 +38,7 @@
    peek-u8 port-open?  port?  positive?  procedure?  quasiquote quote
    quotient raise raise-continuable rational?  rationalize read-bytevector
    read-bytevector!  read-char read-error? read-line read-u8 real?  remainder
-   reverse round set!  set-car!  set-cdr!  string string->list
+   reverse round set!  set-car!  set-cdr!  square string string->list
    string->number string->symbol string->utf8 string->vector string-append
    string-copy string-fill!  string-for-each string-length string-map
    string-ref string-set!  string<=?  string<?  string=?  string>=?