It is a colloquial expression used to indicate that something is in good condition, working properly, or is satisfactory.
Here are some examples of how "theekkanal" might be used:
* "Ninakku theekkanala? (Are you alright?)"
* "Ente kaar theekkanala. (My car is fine/working properly)"
* "Enikku ithu theekkanala. (This is fine for me)"
Essentially, "theekkanal" carries the meaning of being acceptable, satisfactory, and without any issues.