DCHP-1 Online
jam ((n.)) 
1 n. a pile-up of ice-cakes in a river or other narrow watercourse. Also, earlier, spelled jamb.
- 1771 (1792) We had clear water till we passed Camp islands; but on observing a jamb of ice which extended from Table Point towards Belle Isle, we endeavoured to go on the outside of it.
- 1863 . . . for the edges of the vast [ice] field set in motion the previous day had ploughed into the earth, and piled itself in immense angular "jambs."
- 1948 The fast receding water, after the jam had given way, had left bold banks and beaches, piled with ice and debris, in places hundreds of feet high.
2 n. Lumbering a massing together of logs, as in a river drive, as a result of some obstruction to their forward progress.
See also: log-jam (def. 1) timber jam
- 1836 On the morning of the 30th ult, while a canoe with nine men, in the employ of Messrs. Wells and McCrae of this town, were engaged in taking some timber in a jam at the head of Colton's shoots, on the river Madawaska, the canoe unfortunately upset, and seven out of the nine perished.
- 1952 He was in the kitchen . . . that day they were talking about the drive . . . and suddenly he rushed out and broke the jam.
- 1961 Sometimes the key logs of the jam could be pried loose. . . .
- 1771 (1792) We had clear water till we passed Camp islands; but on observing a jamb of ice which extended from Table Point towards Belle Isle, we endeavoured to go on the outside of it.