In practice
A rejection block treats a long wick as a zone. The wick shows where price was pushed back hard, so a return into it is watched for a second reaction in the same direction.
A propulsion block is an order block that forms as price trades back into an earlier order block and then moves away again. Traders read it as the earlier zone being confirmed and use it as a point of interest for continuation.
What to watch for
Both are fine distinctions used by experienced ICT traders. They add little unless the simpler pieces (liquidity, structure and displacement) already point the same way.
Related terms
3 terms- WickThe thin line above or below a candle's body, reaching to its high or low.
- Order blockOBThe last opposite-coloured candle before a displacement that breaks structure; price often reacts when it returns.
- Consequent encroachmentCEThe 50% level of a fair value gap (or of a long wick); healthy gaps tend to hold it.