The most common and most likely answer to this crossword clue is the 3 letter word OHM
I've seen this crossword clue in The Times
O
H
M
More clues leading to the result OHM
- A little resistance from old queen
- Unit giving nothing to Her Majesty
- At last go with mass as a physical unit
- Old, Her Majesty shows some resistance!
- Hug monarch offering little resistance
- Unit expresses surprise with onset of march
- Sacred mantra quelling Henry’s resistance
- Ring the Queen? Some resistance there
- Physicist in love with Her Majesty
- Resistance unit set up in Nottingham house
Buddy explains!

The straight part
We know that "some resistance" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case some resistance = ohm.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does OHM mean?
OHM noun- In the International System of Units, the derived unit of electrical resistance; the electrical resistance of a device across which a potential difference of one volt causes a current of one ampere. Symbol: Ω