What does the phrase thinkest mean?

"Thinkest" is the second-person singular present tense form of the verb "to think", used in older, formal, or poetic English. It's essentially the equivalent of "you think".

Here's a breakdown:

* Think: The verb itself

* Thinkest: The second-person singular present tense (used with "thou")

* Thinks: Third-person singular present tense (used with "he/she/it")

* Think: Third-person plural present tense (used with "they")

* Think: First-person singular or plural present tense (used with "I/we")

* Think: Second-person plural present tense (used with "you")

Here's an example:

* Modern English: "You think you're clever, don't you?"

* Older English: "Thinkest thou art clever, dost thou not?"

Note: "Thinkest" is rarely used in contemporary English, except in highly formal or archaic contexts.