。
The train stopped only briefly.
Literal
Train [topic-は] only a-little stopped.
ほんの ('only, just, a mere') is a pre-nominal modifier that intensifies smallness — 'just a little.' ほんのすこし is a common collocation for 'just a bit, only briefly.' 停車 ('stopping, halting') is the formal noun-verb for vehicles stopping at a point, paired with 発車 (departure).