noun
extra-large portion; super-sized serving
Used primarily in food service contexts (restaurants, cafeterias) to indicate a serving size larger than 大盛 (large). Often the largest size available.
ラーメン屋で特盛を注文したら、麺が山盛りだった。
When I ordered the extra-large portion at the ramen shop, the noodles were piled high.
この店の特盛カレーは普通の２倍の量がある。
The extra-large curry at this restaurant is twice the regular amount.
Compound of 特 (とく, 'special') and 盛 (もり, from 盛る 'to heap up, to serve'), literally 'special heaping'. A relatively modern term used in food service.