Q: Does the word "unit" mean the same thing in "The centimetre is a unit of length." and "The dollar is the United States unit of currency."?

A: the same meaning

Q: Does the word "save" mean the same thing in "This will save money." and "I'll save you the trouble."?

A: the same meaning

Q: Does the word "ply" mean the same thing in "Ply your wits!" and "He plied his trade as carpenter for forty-three years."?

A: the same meaning

Q: Does the word "smile" mean the same thing in "She had a smile on her face." and "He always puts a smile on my face."?

A:
the same meaning