Tip clearance is the distance between the tip of a rotating airfoil and a stationary part.
Gas turbine: Rotor blade and casing Propeller (ship or aircraft): Propeller and structure Ground tip clearance [1] Wind turbine: blade and tower
References
physics
Tip clearance is a physics topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Tip clearance rather than just read about it. In short: Tip clearance is the distance between the tip of a rotating airfoil and a stationary part. Gas turbine: Rotor blade and casing Propeller (ship or aircraft): Propeller and structure Ground tip clearance [1] Wind turbine: blade and tower References

Tip clearance is the distance between the tip of a rotating airfoil and a stationary part.
Gas turbine: Rotor blade and casing Propeller (ship or aircraft): Propeller and structure Ground tip clearance [1] Wind turbine: blade and tower
References

Start with the simplest possible case. Write down what Tip clearance claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In physics, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.
Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Tip clearance before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.
Typical questions about Tip clearance ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.
Tip clearance is the distance between the tip of a rotating airfoil and a stationary part. Gas turbine: Rotor blade and casing Propeller (ship or aircraft): Propeller and structure Ground tip clearance [1] Wind turbine: blade and tower References
Because it connects several physics ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.
Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.
It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Tip clearance.