The definition of glad is feeling pleased, happy, satisfied or grateful.(adjective)
When you are pleased it is not raining, this is an example of a situation where you are glad it is not raining.
See glad in Webster's New World College Dictionary
Origin: ME < OE glæd, akin to Ger glatt, smooth (the orig. Gmc sense) < IE *ghlādh-, shining, smooth < base *ĝhel-, to shine > gleam, gold
See glad in American Heritage Dictionary 4
adjective glad·der, glad·dest
Origin: Middle English
Origin: , from Old English glǽd; see ghel-2 in Indo-European roots.
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