Big head and Head ache

Head ache and big head are semantically related In some cases you can replace phrase "Head ache" with "Big head", this phrases are similar.

Head ache noun - Pain in the head caused by dilation of cerebral arteries or muscle contractions or a reaction to drugs.

Big head and head ache are semantically related in result of heavy drinking topic. Sometimes you can use "Big head" instead a noun phrase "Head ache".