Can you think of any others?

[My Good Babushka]

A contranym is a word with two contrary meanings, like cleave, or sanction.

[rug]

1. oxymoron

sharp, dull

[My Good Babushka]

2. temper

to temper one's words is to soften them, but to temper steel is to harden it.

and

ravel- can mean entangled together, or also frayed apart.

[Glorfindel]

3. Sanction? It can mean both a punishment and an approval

n/t

[intrepidity]

4. Sick?

That's sick! The way kids say it today.

[ailsagirl]

5. Buckle, bolt, finished n/t