1. Gain heat or get hot
   "The room heated up quickly"
   - heat, hot up [Brit] 
2. Make hot or hotter
   - heat 
3. Make more intense
   - hot up [Brit], screw up

Derived forms: heated up, heating up, heats up

Type of: alter, change, change state, compound, deepen, heighten, intensify, modify, turn

• agent-in-place
• agential
• agentive role
• agerasia
• Ageratina
• Ageratina altissima
• ageratum
• Ageratum houstonianum
• Aggeus
• aggie
• agglomerate
• agglomerated
• agglomeration
• agglomerative
• agglomerator
• agglutinate
• agglutinating activity
• agglutination
• agglutination test
• agglutinative
• agglutinin
• agglutinogen
• aggrade
• aggrandise
• aggrandisement