entomology means the scientific study of insects

etymology means the origin of a word

He asked for extra money to tide him over until payday.

It is tide, not tie. The swelling tide will carry you over an obstacle.

Is blest a misspelling of blessed?

That depends.
According to Merriam-Webster’s Online Dictionary it is an alternative.
According to Wiktionary, it is archaic.

To be safe, use blessed.

supposed to means generally considered or expected
This candy is supposed to be good.

supposed to means having an obligation
You are supposed to come with me.

supposed to means intended
The computer was supposed to save us time.

supposed means presumed to be true, but without proof
He is the supposed assailant.

suppose means to theorize (and is never followed by to)
I suppose that is the cause of the problem.

What does TLC stand for?
Tender Loving Care?
Tender Love and Care?

It appears that most sources list Tender Loving Care.

anymore means any longer, nowadays

any more means something additional or further

Here is a different way to look at the meaning of these words:

anybody, anyone, anything, anytime, anywhere
Imply there are many possibilities
Are not selective

somebody, someone, something, sometime, somewhere
Imply there are fewer possibilities
Are selective

For further explanation, visit Grammar Mishaps

When should I hyphenate up to date?

Hyphenate up to date when it precedes a noun.
This is an up-to-date calendar of events.

Do not hyphenate up to date when there is no noun following.
Please keep me up to date on the progress.

somehow means in some way not yet known or designated

anyhow means in any way or manner whatever