In a tv program I saw today the speaker said that Shakespeare had
coined the word "reliance" in one of his works, what is the line, and
which play was it in?

Dear lynda01,

Shakespeare used the word "reliance" only once, in his play "Timon of
Athens" (written around 1607). In Act II, Scene 1, the character of
the Senator says:

"And my reliances on his fracted dates
Have smit my credit: I love and honour him"

Here is the full text of "Timon of Athens", provided by Jeremy
Hylton's site 'The Complete Works of William Shakespeare':
http://www-tech.mit.edu/Shakespeare/timon/full.html


On the website 'OpenSource Shakespeare', Shakespeare's complete
vocabulary is listed; the plural form "reliances" is the only form of
"reliance" Shakespeare used:
http://www.opensourceshakespeare.com/concordance/wordformlist.php?Letter=R


The Online Etymology Dictionary lists 1607 as the year when the word
"reliance" appeared in the English language; this fits with
Shakespeare's play "Timon of Athens":
http://www.etymonline.com/index.php?search=reliance&searchmode=none


Search terms used:
shakespeare reliance
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reliance shakespeare 1607
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shakespeare reliances rely
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reliances shakespeare act scene
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Hope this answers your question!
Regards,
Scriptor

Scriptor is correct. The unabridged Oxford English Dictionary cites
"Timon of Athens" as the first publication of the word.