diff --git a/Modules/zlib/deflate.h b/Modules/zlib/deflate.h
index b16f7a7..05a5ab3 100644
--- a/Modules/zlib/deflate.h
+++ b/Modules/zlib/deflate.h
@@ -188,7 +188,7 @@
     int nice_match; /* Stop searching when current match exceeds this */
 
                 /* used by trees.c: */
-    /* Didn't use ct_data typedef below to suppress compiler warning */
+    /* Didn't use ct_data typedef below to supress compiler warning */
     struct ct_data_s dyn_ltree[HEAP_SIZE];   /* literal and length tree */
     struct ct_data_s dyn_dtree[2*D_CODES+1]; /* distance tree */
     struct ct_data_s bl_tree[2*BL_CODES+1];  /* Huffman tree for bit lengths */
diff --git a/Modules/zlib/gzio.c b/Modules/zlib/gzio.c
index 5cf50e0..7e90f49 100644
--- a/Modules/zlib/gzio.c
+++ b/Modules/zlib/gzio.c
@@ -256,7 +256,7 @@
 /* ===========================================================================
      Read a byte from a gz_stream; update next_in and avail_in. Return EOF
    for end of file.
-   IN assertion: the stream s has been successfully opened for reading.
+   IN assertion: the stream s has been sucessfully opened for reading.
 */
 local int get_byte(s)
     gz_stream *s;
@@ -281,7 +281,7 @@
     mode to transparent if the gzip magic header is not present; set s->err
     to Z_DATA_ERROR if the magic header is present but the rest of the header
     is incorrect.
-    IN assertion: the stream s has already been created successfully;
+    IN assertion: the stream s has already been created sucessfully;
        s->stream.avail_in is zero for the first time, but may be non-zero
        for concatenated .gz files.
 */