Hi Rob,
Welcome to the Community! There are no dumb questions here, especially from newcomers 
See the example below. Let me know if you have questions about the logic.
Note that in your example the lookup value “High Tide” has the 2nd word (Tide) capitalized while in the sample text string it’s not. I’m not sure if it was on purpose or not. In the example I assume that matching and replacement should be case-sensitive.
substring-lookup-replace.morph (3.3 KB)
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