Clock does mean to hit someone when used in slang.
Clocking someone in slang means to hit someone, especially to hit the person on the head or face.
The usage of clocking someone is also often associated with a forceful punch or a blow and it can also mean to knock someone down or stun the person with a hit.
Clock when used as a verb, particularly in informal contexts, means to strike or to hit someone, often with a punch to the persons face.
The slang clock usage is also believed to have originated in Australia and is also linked to the older slang use of clock to mean face.
Clean your clock or even cleaning your clock face are also phrases that are related to the clock meaning face and refer to hitting someone in their face.
And while the "hit" meaning is common, "clock" can also mean to notice or to even observe someone or even to measure time.
To clean her clock means to defeat someone completely in a competition, game etc.
If you're gonna clean her clock then you would usually be defeating someone or trying to defeat someone in a game or competition etc.
If you cleaned someone's clock in a competition, game etc then you have defeated that person.
For example, the lady cleaned our clock in the basketball game.
When a girl says "clock it" it means that the girl has noticed or has observed something.
Other meanings of when a girl says "clock it" are that the girl agrees with or supports a statement that is made by another person.
Or when a girl says "clock it" it can also mean that the girl recognizes or exposes something and it can also be a way of the girl saying "I see it," "I understand," or even "I agree."
Similar to "I see ti" or "I noticed that," saying "clock it" can also be used to acknowledge something that you've observed.
And in some contexts saying "clock it" can also be used to show her agreement with a statement or action such as saying "I agree with that".
And in some cases a girl saying "clock it" can also mean that she has noticed something that another person is trying to keep secret or even hide.
The specific meaning of the girl or someone saying "clock it" can also vary depending on the context of the conversation and the relationship between the speakers.