General understanding:
* Comprehend: This is a strong synonym for "understand," implying a complete grasp of something.
* Grasp: Similar to "comprehend," suggesting a firm mental hold on a concept.
* Perceive: This emphasizes the act of noticing or becoming aware of something.
* Recognize: This focuses on identifying something as known or familiar.
More specific understandings:
* Apprehend: This implies a deeper understanding, often involving the ability to reason or analyze.
* Realize: This focuses on becoming aware of something, often after some thought or reflection.
* Discern: This suggests the ability to distinguish or identify something clearly.
* Know: This implies a certainty about something, often based on experience or knowledge.
The best synonym for "understand" will depend on the specific context and the nuance you want to convey.