Words that have the same pronunciation but different meaning, origin, or spelling.
Homonyms (or if you prefer to be more precise, homophones) aren't phrases of course and as such have no real place on this site. They occur often enough in puns and rhyming slang, like 'scarper' (Scapa Flow), 'mutton' (Mutt'n Jeff) to be worth including though. See also, the common spelling/pronunciation confusion about 'just deserts'.
The most commonly used type of homonym are words that sound the same but have different spelling - known as homophones. There are many pairs of these - 'great' and 'grate', and so on. Less common, but still plentiful, are those words that have the same spelling and pronunciation but different meaning - homographs; for example, those words that exist both as nouns and verbs, like 'fish'.
Of the homonyms that are spelled differently there are many fewer triples than pairs. Less common still are four-word sets. The only ones I know of these are:
Right, write, wright, rite
Raise, rays, raze, rase
Teas, tees, tease, Ts
Seas, sees, seize, Cs
Peek, peak, peke, pique
Pour, pore, paw, poor
Carrot, carat, karat, caret
The first of these the first two seem the nicest. 3,4,5 rely on plurals and the names of letters, which, while being real words, aren't commonly used. 6 depends on a regional pronunciation of 'poor'. That works in some places, but not in most of the English-speaking world, so not everyone would accept it.
Even example 1 isn't 100% 'right'. Most words have a regional pronunciation that make then sound different somewhere, so there probably aren't any four-word homonym groups that work for everyone; for example, 'right' sounds like 'reet' in parts of Scotland.
The solitary goup of five homonyms is (depending on one's allowance of Us, meaning 'the plural of the letter U'):
Use, ewes, yous, Us, yews