Answer:
Repetition is when you make more than once a measurement in a sample.
Replication is when you make a measurement a more than one sample.
Step-by-step explanation:
For example: I have to determine the average weight of beakers. If I weigh 3 times the same beaker, I am doing repetitions (measurements in the same sample). Whit repetitions I can only stimate the measurement instrument error (in this case the error of the used balance).
If I take 3 beakers and weigh them, I have 3 different weigh measurements. These measurements are replicates (measurements in more than one sample). With replicates I can stimate the experiment error (the error associated to the real weight of the beakers).