The clue "Counterpart of effect" is likely looking for the word "cause."
### Explanation:
1. **Understanding the Clue**: In the context of cause and effect, the word "effect" refers to the result or outcome of a particular action, while "cause" is the action or reason behind that outcome. Thus, they are counterparts or opposites in a logical or scientific context.
2. **Wordplay**: Crossword clues often play with language, so recognizing the relationship or opposites can be crucial. Here, you see the direct relationship between cause and effect, making it a straightforward clue.
### Additional Tips for Similar Clues:
- **Identify Relationships**: Look for pairs or concepts that are natural opposites or counterparts, such as cause/effect, light/dark, and up/down.
- **Consider Synonyms**: Sometimes, clues use synonyms or related terms; understanding a range of vocabulary can aid in finding the right answer.
- **Context Clues**: If you have intersecting letters from other clues, they can greatly help in narrowing down the possibilities.
- **Think Broadly**: If you get stuck, take a moment to reconsider the overall theme of the puzzle or even if there’s a pun involved.
This kind of analytical approach can be applied to many clues you may encounter in crossword puzzles.