bloat
To swell too much and feel uncomfortably big or full.
Bloat means to swell up or expand beyond normal size, usually in an uncomfortable or unhealthy way. When you eat too much at Thanksgiving dinner, your stomach might feel bloated: stretched tight and uncomfortably full. A dead fish can wash up on the beach bloated from gases that built up inside it.
The word often carries a negative feeling. Software engineers complain about bloated programs: apps that have grown so large and complicated they run slowly and waste computer memory. A bloated government budget means spending has grown too much. A writer might cut bloat from a story by removing unnecessary words that make sentences puffy and slow.
You can use bloat as a noun too. When a company adds too many features nobody wants, that's called feature bloat. The bloat in your belly after eating three slices of pizza is that overstuffed, slightly queasy sensation.
The key idea is expansion that's gone too far. A balloon filled just right is perfect, but keep blowing and it becomes bloated: stretched thin, ready to pop, no longer quite right.