interpose

To insert something (or oneself) between other things.

to interpose a screen between the eye and the light

What watchful cares do interpose themselves Betwixt your eyes and night?

To interrupt a conversation by introducing a different subject or making a comment.

As one who in his journey bates at Noone, Though bent on speed, so her the Archangel paused Betwixt the world destroyed and world restored, If Adam aught perhaps might interpose; Then with transition sweet new Speech resumes.

“A beautiful country!” “I suppose it is. Everybody says so.” “Your cousin Feenix raves about it, Edith,” interposed her mother from her couch.

To offer (one's help or services).

To be inserted between parts or things; to come between.

Suppose, unlook’d for in a scene so rude, Long hid by interposing hill or wood, Some mansion neat and elegantly dress’d, By some kind hospitable heart possess’d Offer him warmth, security and rest;

To intervene in a dispute, or in a conversation.

The doctor now interposed, and prevented the effects of a wrath which was kindling between Jones and Thwackum […]

"My daughters," replied Sir Thomas, gravely interposing, "have their pleasures at Brighton, and I hope are very happy; […]"