er has definitions from the fields of chemistry,medicine,surgery
1
[ interjection ] interjection, expressing hesitation or hesitancy

Synonyms

gosh umm golly um

2
[ noun ] (medicine,surgery) a room in a hospital or clinic staffed and equipped to provide emergency care to persons requiring immediate medical treatment

Synonyms

emergency_room

3
[ noun ] (chemistry) a trivalent metallic element of the rare earth group; occurs with yttrium
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